by Kipling
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
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Items needed:
-round dowel (wood or rubber) that is the diameter of the pipe (it must fit tightly into the pipe so it doesn't fall out).)
-handlebar grip (the kind used on mountainbike handlebars) basically a long thin tube of rubber that is a fair thickness like that of a handlebar grip.
-pipe approx. 4-6 inches long which is not more than a few millimeters bigger than the handlebar grip in diameter.
- lego tires. the ones from the older lego. They were all one piece and kind of looked like this [ ]------------[ ] the 'rims' that the tires were on were redthe rest of the lego piece was usually black.
Instructions: take the pipe (I used a metal one with the pipe walls being only about a millimeter thickness) and slide the rubber handlebar grip all the way over it so the outside of the pipe is covered with the grip. Now take the lego tires (take them off the lego 'rims'. all you need is the tires themselves) and slide them down the inside of the pipe so they are evenly spaced at approx. half a centimeter from each other all the way down the inside of the pipe.
The tires should be a tight, snug fit as you are pushing down the pipe otherwise they will fall out of the pipe. so choose your pipe diameter accordingly. Leave some space free from lego tires inside the pipe at both ends. you will need to take the dowel (rubber or wood) and drill a hole exactly in the center which is approx. a millemeter bigger than a .22 cal. bullet.
Now you need to force it in one end of the silencer. This will become the "muzzle" (where the bullet comes out)of the silencer. Now wrap masking tape around the end of the barrel of your gun until the diameter of the tape is as thick as the inside diameter of your silencer. Finally you can now slide your silencer onto the end of your gunbarrel. Make sure it is a presice fit and that the muzzle of your gun lines up perfectly with the muzzle of your silencer otherwise the bullet will take the silencer with it next time you fire the gun.
When you fire the gun you will hear a high pitched noise (like a tweet) simmilar to what you hear on movies when someone uses a silencer. This takes approx. a couple hours to make and is fairly easy to make. I got the idea for this from other articles on this website, all I did was try to think of some alternate materials which would be easier to find around the house. But this works really great and you can make a bunch of them really easily and quickly for all your firearms. I only tried it on a .22 LR rifle using supersonic rounds, but I'm sure it would work on other calibers as well as long as you always make sure that the bullet itself is able to easily fit throught all the tires and the end dowel otherwise your silencer will be history the first time you try it.
How to: Weapons
scam lock picking explosives phone phreak hacking, know .
Showing posts with label Weapons. Show all posts
Showing posts with label Weapons. Show all posts
An Aussie Beer Can Mortar
by Andy
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
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Once apon a time well before I was connected to the net........
About Me..
Married, one ruggie, and a military man.
As a mechanical fitter I have been employed many times to manufacture tools and jigs for other tradesmen working in different departments in my unit. I have an interest in firearms (and weapons)of all types. I have used my skills to manufacture model, nad larger cannon as well as helping mates with legal modifications to there firearms. Yes I have also committed the most grevious of sins by de-activating or de-milling other wise serviceable weapons just because they were unfasionable at the time. I will never vote for that government again!!
Well any way one day...
I happened upon a large peice of brass round stock 125mm x 400mm. Too nice to be left lying around, too short for a cannon, just right for a mortar. So a quick look at my reference material and a suitable mortar shape was drawn up, scaled to give the least waste from the raw material... and just the right size to be bored to 62mm. A nice clearence diameter for a Victoria Bitter Beer Can. The exact dimentions of my mortar are unimportant, needless to say that I overengineered to some degree.
The projectile was selected because of:
A, size
b, shape
c, diameter
and, d, abundance!
The brass stock was offered to my trusty lathe and trued up externaly then drilled and bored to size. External dimentions were basic as all a Blackpowder mortar is, is a short, thick tube. The trunnion is located at the base, just the same as the modern stokes mortar, with a wooden carrage.
Mortars and Howitsers have a common theme, use a small powder charge to lob the projectile to the desired range. Many early mortar have huge bore sizes enabling large diameter projectiles to be fired short distances, all that was needed then. In keeping with the mortar theme a powder chamber 30mm in Dia. x 30mm deep was machined into the base of the short barrel.
Initial testing of the mortar with empty and gravel filled beer cans proved dissapointing.
The thinking cap went on and the very next weekend ten concrete filled beer cans were ready for some serious R&D
The Big day (no not Trinity NM 1945) but close!
A blow by blow account by Brat (not his real name)and Andy..
"Will it work this time" Snickered Brat.
"Fu** off Brat, I've just finished greasing the can, it would justabout fit your a** keep it up!" I retorted, we are really good mates!
"Eat me" or words to that effect snapped Brat.
"Is that all the powder you are going to use?" asked Brat
"Is the wick long enough?"
"Should'nt you push the can in more? finished Brat, the expert.
"Who's fu**ing this duck, stand back wicks lit" I replied.
"Shit"
BOOOM..gasp for breath, good shockwave!
The can launched out of that thing like a scalded cat (and we havew seen some oof those), rose to 200 meters, reached apogee (dictonary job) and tumbled into a lake at the 175 meter mark on the range (1/2 way between the turkeys and the rams. The thud of impact was preceded by the 10 meter shower of water glinting in the morning sun.
Just afterwards I was basking in wonder of what I had done, watching the thick cloud of smoke lasily drifd down range when I heared a funny noize...
"Is that you Brat?" I asked
"Mummummf, MMUMMF!"
"Speak up prick!" I replied as I turned to see Brat. His eyes were rolled back, in one bony hand was a beer can, in the other the powder flask and the reason he was incoherent 6" of wick clenched in between his drooling lips.
"OK your turn"
On a more analitical note:
Range at 45 - 55 Deg 180 to 250 meters
Altitude 200 to 250 meters, by eye
F grade Blackpowder only, augmented with homemade stuff to fill the chamber
Only the finest VB cans were used
Lots of Vasiline as lube
Felt wadding
commercial cannon fuse
The bore fouled up quickly, probably because of my blackpowder
Cement (mortar mix) strenghtened the can and increased pressure nicely.
We stood well back!!! and still felt the shock wave.
Standard disclamers, I'm telling a story, not giving instructions!!!
A BEER CAN IN FLIGHT IS A WONDERFUL SIGHT!
AIM
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
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Once apon a time well before I was connected to the net........
About Me..
Married, one ruggie, and a military man.
As a mechanical fitter I have been employed many times to manufacture tools and jigs for other tradesmen working in different departments in my unit. I have an interest in firearms (and weapons)of all types. I have used my skills to manufacture model, nad larger cannon as well as helping mates with legal modifications to there firearms. Yes I have also committed the most grevious of sins by de-activating or de-milling other wise serviceable weapons just because they were unfasionable at the time. I will never vote for that government again!!
Well any way one day...
I happened upon a large peice of brass round stock 125mm x 400mm. Too nice to be left lying around, too short for a cannon, just right for a mortar. So a quick look at my reference material and a suitable mortar shape was drawn up, scaled to give the least waste from the raw material... and just the right size to be bored to 62mm. A nice clearence diameter for a Victoria Bitter Beer Can. The exact dimentions of my mortar are unimportant, needless to say that I overengineered to some degree.
The projectile was selected because of:
A, size
b, shape
c, diameter
and, d, abundance!
The brass stock was offered to my trusty lathe and trued up externaly then drilled and bored to size. External dimentions were basic as all a Blackpowder mortar is, is a short, thick tube. The trunnion is located at the base, just the same as the modern stokes mortar, with a wooden carrage.
Mortars and Howitsers have a common theme, use a small powder charge to lob the projectile to the desired range. Many early mortar have huge bore sizes enabling large diameter projectiles to be fired short distances, all that was needed then. In keeping with the mortar theme a powder chamber 30mm in Dia. x 30mm deep was machined into the base of the short barrel.
Initial testing of the mortar with empty and gravel filled beer cans proved dissapointing.
The thinking cap went on and the very next weekend ten concrete filled beer cans were ready for some serious R&D
The Big day (no not Trinity NM 1945) but close!
A blow by blow account by Brat (not his real name)and Andy..
"Will it work this time" Snickered Brat.
"Fu** off Brat, I've just finished greasing the can, it would justabout fit your a** keep it up!" I retorted, we are really good mates!
"Eat me" or words to that effect snapped Brat.
"Is that all the powder you are going to use?" asked Brat
"Is the wick long enough?"
"Should'nt you push the can in more? finished Brat, the expert.
"Who's fu**ing this duck, stand back wicks lit" I replied.
"Shit"
BOOOM..gasp for breath, good shockwave!
The can launched out of that thing like a scalded cat (and we havew seen some oof those), rose to 200 meters, reached apogee (dictonary job) and tumbled into a lake at the 175 meter mark on the range (1/2 way between the turkeys and the rams. The thud of impact was preceded by the 10 meter shower of water glinting in the morning sun.
Just afterwards I was basking in wonder of what I had done, watching the thick cloud of smoke lasily drifd down range when I heared a funny noize...
"Is that you Brat?" I asked
"Mummummf, MMUMMF!"
"Speak up prick!" I replied as I turned to see Brat. His eyes were rolled back, in one bony hand was a beer can, in the other the powder flask and the reason he was incoherent 6" of wick clenched in between his drooling lips.
"OK your turn"
On a more analitical note:
Range at 45 - 55 Deg 180 to 250 meters
Altitude 200 to 250 meters, by eye
F grade Blackpowder only, augmented with homemade stuff to fill the chamber
Only the finest VB cans were used
Lots of Vasiline as lube
Felt wadding
commercial cannon fuse
The bore fouled up quickly, probably because of my blackpowder
Cement (mortar mix) strenghtened the can and increased pressure nicely.
We stood well back!!! and still felt the shock wave.
Standard disclamers, I'm telling a story, not giving instructions!!!
A BEER CAN IN FLIGHT IS A WONDERFUL SIGHT!
AIM
Jail-bird Ice Pick
by 6ic-Cee
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
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The Jailbird Ice Pick
6-C
There's an ice-pick jailbirds make! Pro-lifers make these and kill each other with this; here's how to make it!
You'll Need:
A little bit of seran wrap or any king of plastic really.
A tooth brush.
Fire.
How to Make: Take the plastic and wrap it around the head of the tooth-brush tightly, put the head into an open flame from, let's say, a lighter untill it catches fire. Let it burn a bit, then, scrape it against the concrete floor untill you have a really sharp tooth-brush
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
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The Jailbird Ice Pick
6-C
There's an ice-pick jailbirds make! Pro-lifers make these and kill each other with this; here's how to make it!
You'll Need:
A little bit of seran wrap or any king of plastic really.
A tooth brush.
Fire.
How to Make: Take the plastic and wrap it around the head of the tooth-brush tightly, put the head into an open flame from, let's say, a lighter untill it catches fire. Let it burn a bit, then, scrape it against the concrete floor untill you have a really sharp tooth-brush
GloveGun
by Corza
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
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GloveGun
Materials:
Small metal Rubber glove fingers Duct tape
Optional: Welder
Step one:
Cut the finger of one ruber glove right down near the base. Get some pipe and make sure its just big enough so that you can strech the glove over it and it stays on.
Step two:
Cut the pipe to about 35 cm and 10 cm for a handle.
Step three:
Cut the end of the handle bit at 45 degrees, then weld it at the very end of the 35cm peice so it is in the shape of a number 7.
Step four:
Duct tape the handle up, and file of any cut ends. Then duct tape a glove finger about 3cms on the end of the pipe.
How to use:
Use fishing sinkers, ball bearings or my prefered ammo, metal nuts about one cm across. You can experiment with ammo and by putting a laser pointer on top but do not use rocks cause they cut up the glove fingers
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
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GloveGun
Materials:
Small metal Rubber glove fingers Duct tape
Optional: Welder
Step one:
Cut the finger of one ruber glove right down near the base. Get some pipe and make sure its just big enough so that you can strech the glove over it and it stays on.
Step two:
Cut the pipe to about 35 cm and 10 cm for a handle.
Step three:
Cut the end of the handle bit at 45 degrees, then weld it at the very end of the 35cm peice so it is in the shape of a number 7.
Step four:
Duct tape the handle up, and file of any cut ends. Then duct tape a glove finger about 3cms on the end of the pipe.
How to use:
Use fishing sinkers, ball bearings or my prefered ammo, metal nuts about one cm across. You can experiment with ammo and by putting a laser pointer on top but do not use rocks cause they cut up the glove fingers
Big Bullets For Beginners
by Anonymous
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
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Big Bullets for Beginners Guns are generally classified according to use, size, and tradition. This varies among the military services. The basic distinction is between small arms and artillery. Any gun below a 20- millimeter bore size is generally classified as a small arm. The Army distinguishes among mortars, howitzers, and guns.
Mortars give high trajectories with short range and are usually loaded from the muzzle. Howitzers give medium-to-high trajectories, and guns provide flat-to-medium trajectories of longer range. Bore size is usually given in millimeters.
A gun can be considered as a particular kind of heat engine. In operation, the propellant charge located in the gun chamber is ignited by the primer. Gases produced by combustion of the propellant grains cause a rapid buildup of pressure. When a certain pressure is reached (shot-start pressure) which overcomes the forces of projectile weight and engraving of the projectile in the rifling, the projectile begins to move toward the muzzle which causes an increase in chamber volume. A maximum pressure is reached a few inches from the origin of rifling followed by a decrease in pressure all the way to the muzzle. At the muzzle, the pressure is 10 percent to 30 percent of the maximum pressure, depending on the geometry of the propellant grains.
Artillery ammunition can be classified in many ways. One classification is based on the manner in which the components are assembled for loading and firing. Complete rounds of artillery ammunition are known as either semi-fixed or separate loading. In contrast, small arms rounds are FIXED ammunition, with which it is not possible to adjust the amount of propellant in the cartridge case).
Semi-fixed ammunition is characterized by an adjustable propelling charge. The propellant is divided into increments, or charges, and each increment of propellant is contained in a cloth bag. All of the cloth bags are held together by an acrylic cord, and are stored in the cartridge case. The primer is an integral part of the cartridge case, and is located on the base. Semi-fixed ammunition may be issued fuzed or unfuzed. Semi-fixed ammunition is used in 105mm howitzers. The ammunition is shipped in a wooden crate, with two fiber tubes in each crate. The fiber tubes are sealed at each end with tape. Upon removing the tape, the cannoneer will place the heavy end down first, and remove the projectile from the fiber tube. Next, the cartridge case is removed. Both the projectile and canister MUST REMAIN in their fiber cups until firing. Separate loading ammunition has four separate components: primer, propellant, projectile, and fuze. The four components are issued separately. Upon preparation for firing, the projectile and propellant are loaded into the howitzer in two separate operations. Separate loading ammunition is used in 155mm howitzers.
There are two explosive trains in each conventional round of artillery ammunition; the PROPELLING CHARGE EXPLOSIVE TRAIN, and the PROJECTILE EXPLOSIVE TRAIN. The projectile reaches the target area by the power obtained from the propelling charge explosive train. The function of the projectile in the target area depends on the type of projectile explosive train.
The propelling charge explosive train consists of the primer, igniter, and propellant. The propelling charge explosive train is initiated by the primer, which is a small amount of very sensitive explosive. The primer is very sensitive to shock, friction, spark, and heat, and must be kept protected and away from other ammunition components. In separate loading ammunition, the primer is a separate item of issue. The igniter provides hot flaming gases and particles to ignite the propelling charge. The igniter consists of black powder or Clean Burning Igniter (CBI). The igniter is very hygroscopic and subject to rapid deterioration on absorption of moisture. If kept dry, however, it retains its explosive properties indefinitely. The igniter for semi-fixed ammunition is an integral part of the primer. It consists of a perforated tube filled with black powder and is permanently mounted in the cartridge case. In separate loading ammunition, the igniter is in a circular red pancake shaped bag sewn to the base increment of the propellant. When ignited by the primer, the igniter sends hot flaming gases around the charge to ignite the propellant.
A propellant is a large amount of insensitive but powerful explosive that propels the projectile to the target. Semi-fixed ammunition propellant is generally issued with seven increments numbered 1 through 7, and connected by a thin acrylic cord. Each increment is a different size because each increment has a different premeasured amount of propellant. Increment 1 and 2 are single perforated and increments 3-7 are multi-perforated. Separate loading ammunition propellants are issued as a separate unit of issue in sealed canisters to protect the propellant. The amount of propellant to be fired with artillery ammunition is varied by the number of propellant increments. The charge selected is based on the range to the target and the tactical situation.
Projectile Design
Since the first projectile was manufactured, the demand for greater accuracy and greater range has influenced projectile design. Without specifically constructed shapes and exterior parts, there would be no standard ballistic characteristics for any group or type of projectiles. A lack of ballistic standardization would prevent the computation of firing tables. Modern projectiles are designed for maximum stability and minimum air resistance in flight.
Eyebolt Lifting Plugs and Fuze Well Plugs. A separate-loading projectile has an eyebolt lifting plug. Other types of projectiles have metal hex-head or plastic closing plugs. The plug is for lifting; to keep the fuze well clean, dry, and free of foreign matter; and to protect the fuze well threads. The plug is removed, and the appropriate fuze is inserted at the firing position. Some special-purpose semifixed projectiles are issued with the fuzes already assembled in the projectile.
Ogive. The ogive is the curved portion of a projectile between the fuze well and the bourrelet. It streamlines the forward portion of the projectile. The curve of the ogive usually is the arc of the circle, the center of which is located in a line perpendicular to the axis of the projectile and the radius of which is generally 6 to 11 calibers.
Bourrelet. The bourrelet is an accurately machined surface that is slightly larger than the body and located immediately to the rear of the ogive. It centers the forward part of the projectile in the tube and bears on the lands of the tube. When the projectile travels through the bore, only the bourrelet and the rotating band of the projectile bear on the lands of the tube.
Body. The body is the cylindrical portion of the projectile between the bourrelet and the rotating band. It is machined to a smaller diameter than the bourrelet to reduce the projectile surface in contact with the lands of the bore. The body contains most of the projectile filler.
Rotating Band. The rotating band is a cylindrical ring of comparatively soft metal that is pressed into a knurled, or roughened, groove near the base of the projectile. It mates with the forcing cone of the tube to eliminate gas wash (blow-by) and to provide forward obturation. The rotating band, in conjunction with the rifling of the tube, imparts spin to the moving projectile. A properly rammed separate-loading projectile is held in the tube at all angles of elevation by the wedging action of the rotating band against the forcing cone.
Obturating Band. On some projectiles, there is a nylon obturating band below the rotating band to help in forward obturation. Two examples of 155-mm projectiles with this type of a band are the illuminating round and the high-explosive rocket-assisted round.
Base. The base is that portion of the projectile below the rotating band or obturating band. The most common type is known as the boattail base. This type of base streamlines the base of the projectile, gives added stability in flight, and minimizes deceleration by reducing the vacuum-forming eddy currents in the wake of the projectile as it passes through the atmosphere.
Base Cover. The base cover is a metal cover that is crimped, caulked or welded to the base of the projectile. It prevents hot gases of the propelling charge from coming in contact with the explosive filler of the projectile through possible flaws in the metal of the base.
Large Caliber Ammunition - Types of Projectiles
Projectiles can be broadly classified according to three main types: spin-stabilized, fin-stabilized, and rocket assisted (both fin- and spin-stabilized). Formal military classification is based on the intended use of the projectile and the composition of the explosive charge (i.e., antipersonnel, antitank, and incendiary). Some very significant progress in projectile design has been made in the past few years.
SPIN-STABILIZED PROJECTILES Most guns in use today use spin-stabilized projectiles. Spinning a projectile promotes flight stability. Spinning is obtained by firing the projectiles through a rifled tube. The projectile engages the rifling by means of a rotating band normally made of copper. The rotating band is engaged by the lands and grooves. At a nominal muzzle velocity of 2800 feet per second, spin rates on the order of 250 revolutions per second are encountered. Spin-stabilized projectiles are full bore (flush with the bore walls) and are limited approximately to a 5:1 length-to-diameter ratio. They perform very well at relatively low trajectories (less than 45° quadrant elevation). In high trajectory applications they tend to overstabilize (maintain the angle at which they were fired) and, therefore, do not follow the trajectory satisfactorily.
FIN-STABILIZED PROJECTILES These projectiles obtain stability through the use of fins located at the aft end of the projectile. Normally, four to six fins are employed. Additional stability is obtained by imparting some spin (approximately 20 revolutions/second) to the projectile by canting the leading edge of the fins. Fin-stabilized projectiles are very often subcaliber. A sabot, wood or metal fitted around the projectile, is used to center the projectile in the bore and provide a gas seal. Such projectiles vary from 10:1 to 15:1 in length-to-diameter ratio. Fin-stabilized projectiles are advantageous because they follow the trajectory very well at high-launch angles, and they can be designed with very low drag thereby increasing range and/or terminal velocity. However, fin-stabilized projectiles are disadvantageous because the extra length of the projectile must be accommodated and the payload volume is comparatively low in relation to the projectile length.
ROCKET-ASSISTED PROJECTILES There are two main reasons for developing rocket-assisted projectiles: (1) to extend the range over standard gun systems, and (2) to allow for lighter mount and barrel design and reduce excessive muzzle flash and smoke by reducing the recoil and setback forces of standard gun systems. Since the ranges are different, the above two objectives represent opposite approaches in the development of rocket-assisted projectiles. Normally, one or the other establishes the performance of the rocket-assisted projectile under development although some compromise in the two approaches may be established by the design objectives.
Large Caliber Ammunition - Types of Warhead
For convenience of discussion, large caliber ammunition may be be classified into five major groups: blast (including air and underwater burst), fragmentation, shaped charge, pyrotechnics, and cluster.
Blast
A blast warhead is one that is designed to achieve target damage primarily from blast effect. When a high explosive detonates, it is converted almost instantly into a gas at very high pressure and temperature. Under the pressure of the gases thus generated, the weapon case expands and breaks into fragments. The air surrounding the casing is compressed and a shock (blast) wave is transmitted into it. Typical initial values for a high-explosive weapon are 200 kilobars of pressure (1 bar = 1 atmosphere) and 5,000 degrees celsius. The energetic materials used by Department of Defense munitions produce an exothermic reaction defined either as a deflagration or a detonation. A deflagration is an exothermic reaction that propagates from the burning gases to the unreacted material by conduction, convection, and radiation. In this process, the combustion zone progresses through the material at a rate that is less than the velocity of sound in the unreacted material.
In contrast, a detonation is an exothermic reaction that is characterized by the presence of a shock wave in the material that establishes and maintains the reaction. A distinctive difference is that the reaction zone propagates at a rate greater than sound velocity in the unreacted material. Every material capable of detonating has a characteristic velocity that is under fixed conditions of composition, temperature, and density.
The violent release of energy from a detonation in a gaseous medium gives a sudden pressure increase in that medium. The pressure disturbance, termed the blast wave, is characterized by an almost instantaneous rise from the ambient pressure to a peak incident pressure (Pso). This pressure increase, or shock front, travels radially from the burst point with a diminishing velocity that always is in excess of the sonic velocity of the medium. Gas molecules making up the front move at lower velocities. This latter particle velocity is associated with a "dynamic pressure," or the pressure formed by the winds produced by the shock front.
As the shock front expands into increasingly larger volumes of the medium, the peak incident pressure at the front decreases and the duration of the pressure increases. If the shock wave impinges on a rigid surface oriented at an angle to the direction of propagation of the wave, a reflected pressure is instantly developed on the surface and the pressure is raised to a value that exceeds the incident pressure. The reflected pressure is a function of the pressure in the incident wave and the angle formed between the rigid surface and the plane of the shock front.
When an explosion occurs within a structure, the peak pressure associated with the initial shock front will be extremely high and, in turn, will be amplified by reflections within the structure. In addition, the accumulation of gases from the explosion will exert additional pressures and increase the load duration within the structure. The combined effects of both pressures eventually may destroy the structure if it is not strengthened sufficiently or adequate venting for the gas and the shock pressure is not provided, or both. For structures that have one or more strengthened walls, venting for relief of excessive gas or shock pressures, or both, may be provided by means of openings in or frangible construction of the remaining walls or roof, or both. This type of construction will permit the blast wave from an internal explosion to spill over onto the exterior ground surface. These pressures, referred to as exterior or leakage pressures, once released from their confinement, expand radially and act on structures or persons, or both, on the other side of the barrier.
Conventional structures are designed to withstand roof snow loads of 30 pounds per square foot (1.44 kilopascals) and wind loads of 100 miles per hour (161 kilometers per hour). The loads equate to 0.2 pounds per square inch (psi). An important consideration in the analysis of explosions is the effect of the fragments generated by the explosion. These fragments are known as primary or secondary fragments depending on their origin. Primary fragments are formed as a result of the shattering of the casing of conventional munitions. These fragments usually are small in size and travel initially at velocities of the order of thousands of feet per second. Secondary fragments are formed as a result of high blast pressures on structural components and items in close proximity to the explosion. These fragments are somewhat larger in size than primary fragments and travel initially at velocities in the order of hundreds of feet per second. A hazardous fragment is one having an impact energy of 58 ft-lb (79 joules) or greater.
Fragmentation
The study of ballistics, the science of the motion of projectiles, has contributed significantly to the design of fragmentation warheads. Specifically, terminal ballistics studies attempt to determine the laws and conditions governing the velocity and distribution of fragments, the sizes and shapes that result from bursting different containers, and the damage aspects of the bursting charge fragmentation.
Approximately 30% of the energy released by the explosive detonation is used to fragment the case and impart kinetic energy to the fragments. The balance of available energy is used to create a shock front and blast effects. The fragments are propelled at high velocity, and after a short distance they overtake and pass through the shock wave. The rate at which the velocity of the shock front accompanying the blast decreases is generally much greater than the decrease in velocity of fragments, which occurs due to air friction. Therefore, the advance of the shock front lags behind that of the fragments. The radius of effective fragment damage, although target dependent, thus exceeds consid-erably the radius of effective blast damage in an air burst.
Whereas the effects of an idealized blast payload are attenuated by a factor roughly equal to 1/R3 (R is measured from the origin), the attenuation of idealized fragmentation effects will vary as 1/R2 and 1/R, depending upon the specific design of the payload. Herein lies the principle advantage of a fragment-ation payload: it can afford a greater miss distance and still remain effective because its attenuation is less.
Anti-personnel fragmentation munitions are designed to destroy or maim personnel or to damage material enough to render it inoperable. In the area of field artillery, the flechette or beehive round is an example of an anti-personnel warhead. The payload in this projectile consists of 8,000 steel-wire, fin-stabilized darts. Upon detonation the darts, or flechettes, are sprayed radially from the point of detonation, normally within sixty feet of the ground. It is extremely effective against personnel in the open or in dense foliage.
Shaped Charge
The discovery of what is variously referred to as the shaped charge effect, the hollow charge effect, the cavity effect, or the Munroe effect, dates back to the 1880s in this country. Dr. Charles Munroe, while working at the Naval Torpedo Station at Newport, Rhode Island, in the 1880s, discovered that if a block of guncotton with letters countersunk into its surface was det-onated with its lettered surface against a steel plate, the let-ters were indented into the surface of the steel. The essential features of this effect were also observed in about 1880 in both Germany and Norway, although no great use was made of it, and it was temporarily forgotten.
A shaped charge warhead consists basically of a hollow liner of metal material, usually copper or aluminum of conical, hemispherical, or other shape, backed on the convex side by explosive. A container, fuze, and detonating device are included.
When this warhead strikes a target, the fuze detonates the charge from the rear. A detonation wave sweeps forward and begins to collapse the metal cone liner at its apex. The collapse of the cone results in the formation and ejection of a continuous high-velocity molten jet of liner material. Velocity of the tip of the jet is on order of 8,500 meters per sec, while the trail-ing end of the jet has a velocity on the order of 1,500 meters per sec. This produces a velocity gradient that tends to stretch out or lengthen the jet. The jet is then followed by a slug that consists of about 80% of the liner mass. The slug has a velocity on the order of 600 meters per sec.
When the jet strikes a target of armor plate or mild steel, pressures in the range of hundreds of kilobars are produced at the point of contact. This pressure produces stresses far above the yield strength of steel, and the target material flows like a fluid out of the path of the jet. This phenomenon is called hydrodynamic penetration. There is so much radial momentum associated with the flow that the difference in diameter between the jet and the hole it produces depends on the characteristics of the target material. A larger diameter hole will be made in mild steel than in armor plate because the density and hardness of armor plate is greater. The depth of penetration into a very thick slab of mild steel will also be greater than that into homogeneous armor.
In general, the depth of penetration depends upon five factors:
Length of jet
Density of the target material
Hardness of target material
Density of the jet
Jet precision (straight vs. divergent)
The longer the jet, the greater the depth of penetration. Therefore, the greater the standoff distance (distance from target to base of cone) the better. This is true up to the point at which the jet particulates or breaks up (at 6 to 8 cone diameters from the cone base). Particulation is a result of the velocity gradient in the jet, which stretches it out until it breaks up. Jet precision refers to the straightness of the jet. If the jet is formed with some oscillation or wavy motion, then depth of penetration will be reduced. This is a function of the quality of the liner and the initial detonation location accuracy. The effectiveness of shaped charge warheads is reduced when they are caused to rotate. Spin-stabilized projectiles generally cannot use shaped-charge warheads.
Pyrotechnics
Pyrotechnics are typically employed for signaling, illuminating, or marking targets.
Illumination--These warheads usually contain a flare or magnesium flare candle as the payload, which is expelled by a small charge and is parachuted to the ground. During its descent the flare is kindled. The illuminating warhead is thus of great usefulness during night attacks in pointing out enemy fortifications. Because these flares are difficult to extinguish if accidentally ignited, extreme caution in their handling is required.
Smoke--These munitions are used primarily to screen troop movements and play a vital role in battlefield tactics. A black powder charge ignites and expels canisters that may be designed to emit white, yellow, red, green, or violet smoke.
Markers--White phosphorus is commonly employed as a pay-load to mark the position of the enemy. It can be very dangerous, especially in heavy concentrations. The material can self-ignite in air, cannot be extinguished by water, and will rekindle upon subsequent exposure to air. Body contact can produce serious burns. Copper sulphate prevents its re-ignition.
Cluster
Cluster munitions are canisters containing dozens or hundreds of small bomblets for use against a variety of targets, such as personnel, armored ve-hicles, or ships. Once in the air, the canisters open, spreading the bomblets out in a wide pattern. The advantage of this type of warhead is that it gives a wide area of coverage, which allows for a greater margin of error in delivery.
Flechettes
Flechettes are fin stabilized steel projectiles similar in appearance to arrows. During the Korean War the Chinese army tactic of human wave attacks against US lines of defence prompted interest in flechette projectiles in single and multiple projectile systems for small arms and antipersonnel (APERS) use. Flechettes have a performance criteria very different from the conventional rifle bullet. Typical modern flechettes are small light weight steel projectiles, and the velocity lost to air resistance is generally 375 fps. per 100 Meters of flight. Unlike rifle bullets, flechettes are not spin stabilized, but use fins to achieve level flight. The flechette's long body looses rigidity on target impact and bends into a hook, often breaking off the fin portion creating an additional wound. Flechette munitions include projectiles for use in the M16 rifle, CAWS (close assault weapons system), and 12 gage shotgun, as well as the 105mm M101A1/M102 howitzer, 2.75 in. FFAR (folding fin aircraft rocket), and the 70mm Hydra-70 FFAR.
Painting and marking
All projectiles are painted, both as a means of ready identification and as a rust preventative. The basic colors used for many years were olive drab (OD) for high-explosive rounds, gray for chemical rounds, blue for practice rounds, and black for drill rounds. A system of contrasting color markings or bands in addition to the basic color has also been used to identify the particular type of high explosive or chemical used as a filler. Color coding of recently produced projectiles is somewhat different. For example, illuminating and smoke rounds are no longer painted gray, the basic color for chemical shells. Illuminating rounds are now painted basically white or olive drab, and the smoke rounds are painted green. The basic color for dummy ammunition has been changed to bronze. Projectiles containing high explosive TNT Amatol, etc.) are painted yellow. Projectiles containing chemicals (gas or smoke) are painted blue-gray. Projectiles containing low explosives (black powder) are painted red. Projectiles are also stenciled to show the caliber, type of cannon used in, ammunition lot number, kind of filling, etc
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Big Bullets for Beginners Guns are generally classified according to use, size, and tradition. This varies among the military services. The basic distinction is between small arms and artillery. Any gun below a 20- millimeter bore size is generally classified as a small arm. The Army distinguishes among mortars, howitzers, and guns.
Mortars give high trajectories with short range and are usually loaded from the muzzle. Howitzers give medium-to-high trajectories, and guns provide flat-to-medium trajectories of longer range. Bore size is usually given in millimeters.
A gun can be considered as a particular kind of heat engine. In operation, the propellant charge located in the gun chamber is ignited by the primer. Gases produced by combustion of the propellant grains cause a rapid buildup of pressure. When a certain pressure is reached (shot-start pressure) which overcomes the forces of projectile weight and engraving of the projectile in the rifling, the projectile begins to move toward the muzzle which causes an increase in chamber volume. A maximum pressure is reached a few inches from the origin of rifling followed by a decrease in pressure all the way to the muzzle. At the muzzle, the pressure is 10 percent to 30 percent of the maximum pressure, depending on the geometry of the propellant grains.
Artillery ammunition can be classified in many ways. One classification is based on the manner in which the components are assembled for loading and firing. Complete rounds of artillery ammunition are known as either semi-fixed or separate loading. In contrast, small arms rounds are FIXED ammunition, with which it is not possible to adjust the amount of propellant in the cartridge case).
Semi-fixed ammunition is characterized by an adjustable propelling charge. The propellant is divided into increments, or charges, and each increment of propellant is contained in a cloth bag. All of the cloth bags are held together by an acrylic cord, and are stored in the cartridge case. The primer is an integral part of the cartridge case, and is located on the base. Semi-fixed ammunition may be issued fuzed or unfuzed. Semi-fixed ammunition is used in 105mm howitzers. The ammunition is shipped in a wooden crate, with two fiber tubes in each crate. The fiber tubes are sealed at each end with tape. Upon removing the tape, the cannoneer will place the heavy end down first, and remove the projectile from the fiber tube. Next, the cartridge case is removed. Both the projectile and canister MUST REMAIN in their fiber cups until firing. Separate loading ammunition has four separate components: primer, propellant, projectile, and fuze. The four components are issued separately. Upon preparation for firing, the projectile and propellant are loaded into the howitzer in two separate operations. Separate loading ammunition is used in 155mm howitzers.
There are two explosive trains in each conventional round of artillery ammunition; the PROPELLING CHARGE EXPLOSIVE TRAIN, and the PROJECTILE EXPLOSIVE TRAIN. The projectile reaches the target area by the power obtained from the propelling charge explosive train. The function of the projectile in the target area depends on the type of projectile explosive train.
The propelling charge explosive train consists of the primer, igniter, and propellant. The propelling charge explosive train is initiated by the primer, which is a small amount of very sensitive explosive. The primer is very sensitive to shock, friction, spark, and heat, and must be kept protected and away from other ammunition components. In separate loading ammunition, the primer is a separate item of issue. The igniter provides hot flaming gases and particles to ignite the propelling charge. The igniter consists of black powder or Clean Burning Igniter (CBI). The igniter is very hygroscopic and subject to rapid deterioration on absorption of moisture. If kept dry, however, it retains its explosive properties indefinitely. The igniter for semi-fixed ammunition is an integral part of the primer. It consists of a perforated tube filled with black powder and is permanently mounted in the cartridge case. In separate loading ammunition, the igniter is in a circular red pancake shaped bag sewn to the base increment of the propellant. When ignited by the primer, the igniter sends hot flaming gases around the charge to ignite the propellant.
A propellant is a large amount of insensitive but powerful explosive that propels the projectile to the target. Semi-fixed ammunition propellant is generally issued with seven increments numbered 1 through 7, and connected by a thin acrylic cord. Each increment is a different size because each increment has a different premeasured amount of propellant. Increment 1 and 2 are single perforated and increments 3-7 are multi-perforated. Separate loading ammunition propellants are issued as a separate unit of issue in sealed canisters to protect the propellant. The amount of propellant to be fired with artillery ammunition is varied by the number of propellant increments. The charge selected is based on the range to the target and the tactical situation.
Projectile Design
Since the first projectile was manufactured, the demand for greater accuracy and greater range has influenced projectile design. Without specifically constructed shapes and exterior parts, there would be no standard ballistic characteristics for any group or type of projectiles. A lack of ballistic standardization would prevent the computation of firing tables. Modern projectiles are designed for maximum stability and minimum air resistance in flight.
Eyebolt Lifting Plugs and Fuze Well Plugs. A separate-loading projectile has an eyebolt lifting plug. Other types of projectiles have metal hex-head or plastic closing plugs. The plug is for lifting; to keep the fuze well clean, dry, and free of foreign matter; and to protect the fuze well threads. The plug is removed, and the appropriate fuze is inserted at the firing position. Some special-purpose semifixed projectiles are issued with the fuzes already assembled in the projectile.
Ogive. The ogive is the curved portion of a projectile between the fuze well and the bourrelet. It streamlines the forward portion of the projectile. The curve of the ogive usually is the arc of the circle, the center of which is located in a line perpendicular to the axis of the projectile and the radius of which is generally 6 to 11 calibers.
Bourrelet. The bourrelet is an accurately machined surface that is slightly larger than the body and located immediately to the rear of the ogive. It centers the forward part of the projectile in the tube and bears on the lands of the tube. When the projectile travels through the bore, only the bourrelet and the rotating band of the projectile bear on the lands of the tube.
Body. The body is the cylindrical portion of the projectile between the bourrelet and the rotating band. It is machined to a smaller diameter than the bourrelet to reduce the projectile surface in contact with the lands of the bore. The body contains most of the projectile filler.
Rotating Band. The rotating band is a cylindrical ring of comparatively soft metal that is pressed into a knurled, or roughened, groove near the base of the projectile. It mates with the forcing cone of the tube to eliminate gas wash (blow-by) and to provide forward obturation. The rotating band, in conjunction with the rifling of the tube, imparts spin to the moving projectile. A properly rammed separate-loading projectile is held in the tube at all angles of elevation by the wedging action of the rotating band against the forcing cone.
Obturating Band. On some projectiles, there is a nylon obturating band below the rotating band to help in forward obturation. Two examples of 155-mm projectiles with this type of a band are the illuminating round and the high-explosive rocket-assisted round.
Base. The base is that portion of the projectile below the rotating band or obturating band. The most common type is known as the boattail base. This type of base streamlines the base of the projectile, gives added stability in flight, and minimizes deceleration by reducing the vacuum-forming eddy currents in the wake of the projectile as it passes through the atmosphere.
Base Cover. The base cover is a metal cover that is crimped, caulked or welded to the base of the projectile. It prevents hot gases of the propelling charge from coming in contact with the explosive filler of the projectile through possible flaws in the metal of the base.
Large Caliber Ammunition - Types of Projectiles
Projectiles can be broadly classified according to three main types: spin-stabilized, fin-stabilized, and rocket assisted (both fin- and spin-stabilized). Formal military classification is based on the intended use of the projectile and the composition of the explosive charge (i.e., antipersonnel, antitank, and incendiary). Some very significant progress in projectile design has been made in the past few years.
SPIN-STABILIZED PROJECTILES Most guns in use today use spin-stabilized projectiles. Spinning a projectile promotes flight stability. Spinning is obtained by firing the projectiles through a rifled tube. The projectile engages the rifling by means of a rotating band normally made of copper. The rotating band is engaged by the lands and grooves. At a nominal muzzle velocity of 2800 feet per second, spin rates on the order of 250 revolutions per second are encountered. Spin-stabilized projectiles are full bore (flush with the bore walls) and are limited approximately to a 5:1 length-to-diameter ratio. They perform very well at relatively low trajectories (less than 45° quadrant elevation). In high trajectory applications they tend to overstabilize (maintain the angle at which they were fired) and, therefore, do not follow the trajectory satisfactorily.
FIN-STABILIZED PROJECTILES These projectiles obtain stability through the use of fins located at the aft end of the projectile. Normally, four to six fins are employed. Additional stability is obtained by imparting some spin (approximately 20 revolutions/second) to the projectile by canting the leading edge of the fins. Fin-stabilized projectiles are very often subcaliber. A sabot, wood or metal fitted around the projectile, is used to center the projectile in the bore and provide a gas seal. Such projectiles vary from 10:1 to 15:1 in length-to-diameter ratio. Fin-stabilized projectiles are advantageous because they follow the trajectory very well at high-launch angles, and they can be designed with very low drag thereby increasing range and/or terminal velocity. However, fin-stabilized projectiles are disadvantageous because the extra length of the projectile must be accommodated and the payload volume is comparatively low in relation to the projectile length.
ROCKET-ASSISTED PROJECTILES There are two main reasons for developing rocket-assisted projectiles: (1) to extend the range over standard gun systems, and (2) to allow for lighter mount and barrel design and reduce excessive muzzle flash and smoke by reducing the recoil and setback forces of standard gun systems. Since the ranges are different, the above two objectives represent opposite approaches in the development of rocket-assisted projectiles. Normally, one or the other establishes the performance of the rocket-assisted projectile under development although some compromise in the two approaches may be established by the design objectives.
Large Caliber Ammunition - Types of Warhead
For convenience of discussion, large caliber ammunition may be be classified into five major groups: blast (including air and underwater burst), fragmentation, shaped charge, pyrotechnics, and cluster.
Blast
A blast warhead is one that is designed to achieve target damage primarily from blast effect. When a high explosive detonates, it is converted almost instantly into a gas at very high pressure and temperature. Under the pressure of the gases thus generated, the weapon case expands and breaks into fragments. The air surrounding the casing is compressed and a shock (blast) wave is transmitted into it. Typical initial values for a high-explosive weapon are 200 kilobars of pressure (1 bar = 1 atmosphere) and 5,000 degrees celsius. The energetic materials used by Department of Defense munitions produce an exothermic reaction defined either as a deflagration or a detonation. A deflagration is an exothermic reaction that propagates from the burning gases to the unreacted material by conduction, convection, and radiation. In this process, the combustion zone progresses through the material at a rate that is less than the velocity of sound in the unreacted material.
In contrast, a detonation is an exothermic reaction that is characterized by the presence of a shock wave in the material that establishes and maintains the reaction. A distinctive difference is that the reaction zone propagates at a rate greater than sound velocity in the unreacted material. Every material capable of detonating has a characteristic velocity that is under fixed conditions of composition, temperature, and density.
The violent release of energy from a detonation in a gaseous medium gives a sudden pressure increase in that medium. The pressure disturbance, termed the blast wave, is characterized by an almost instantaneous rise from the ambient pressure to a peak incident pressure (Pso). This pressure increase, or shock front, travels radially from the burst point with a diminishing velocity that always is in excess of the sonic velocity of the medium. Gas molecules making up the front move at lower velocities. This latter particle velocity is associated with a "dynamic pressure," or the pressure formed by the winds produced by the shock front.
As the shock front expands into increasingly larger volumes of the medium, the peak incident pressure at the front decreases and the duration of the pressure increases. If the shock wave impinges on a rigid surface oriented at an angle to the direction of propagation of the wave, a reflected pressure is instantly developed on the surface and the pressure is raised to a value that exceeds the incident pressure. The reflected pressure is a function of the pressure in the incident wave and the angle formed between the rigid surface and the plane of the shock front.
When an explosion occurs within a structure, the peak pressure associated with the initial shock front will be extremely high and, in turn, will be amplified by reflections within the structure. In addition, the accumulation of gases from the explosion will exert additional pressures and increase the load duration within the structure. The combined effects of both pressures eventually may destroy the structure if it is not strengthened sufficiently or adequate venting for the gas and the shock pressure is not provided, or both. For structures that have one or more strengthened walls, venting for relief of excessive gas or shock pressures, or both, may be provided by means of openings in or frangible construction of the remaining walls or roof, or both. This type of construction will permit the blast wave from an internal explosion to spill over onto the exterior ground surface. These pressures, referred to as exterior or leakage pressures, once released from their confinement, expand radially and act on structures or persons, or both, on the other side of the barrier.
Conventional structures are designed to withstand roof snow loads of 30 pounds per square foot (1.44 kilopascals) and wind loads of 100 miles per hour (161 kilometers per hour). The loads equate to 0.2 pounds per square inch (psi). An important consideration in the analysis of explosions is the effect of the fragments generated by the explosion. These fragments are known as primary or secondary fragments depending on their origin. Primary fragments are formed as a result of the shattering of the casing of conventional munitions. These fragments usually are small in size and travel initially at velocities of the order of thousands of feet per second. Secondary fragments are formed as a result of high blast pressures on structural components and items in close proximity to the explosion. These fragments are somewhat larger in size than primary fragments and travel initially at velocities in the order of hundreds of feet per second. A hazardous fragment is one having an impact energy of 58 ft-lb (79 joules) or greater.
Fragmentation
The study of ballistics, the science of the motion of projectiles, has contributed significantly to the design of fragmentation warheads. Specifically, terminal ballistics studies attempt to determine the laws and conditions governing the velocity and distribution of fragments, the sizes and shapes that result from bursting different containers, and the damage aspects of the bursting charge fragmentation.
Approximately 30% of the energy released by the explosive detonation is used to fragment the case and impart kinetic energy to the fragments. The balance of available energy is used to create a shock front and blast effects. The fragments are propelled at high velocity, and after a short distance they overtake and pass through the shock wave. The rate at which the velocity of the shock front accompanying the blast decreases is generally much greater than the decrease in velocity of fragments, which occurs due to air friction. Therefore, the advance of the shock front lags behind that of the fragments. The radius of effective fragment damage, although target dependent, thus exceeds consid-erably the radius of effective blast damage in an air burst.
Whereas the effects of an idealized blast payload are attenuated by a factor roughly equal to 1/R3 (R is measured from the origin), the attenuation of idealized fragmentation effects will vary as 1/R2 and 1/R, depending upon the specific design of the payload. Herein lies the principle advantage of a fragment-ation payload: it can afford a greater miss distance and still remain effective because its attenuation is less.
Anti-personnel fragmentation munitions are designed to destroy or maim personnel or to damage material enough to render it inoperable. In the area of field artillery, the flechette or beehive round is an example of an anti-personnel warhead. The payload in this projectile consists of 8,000 steel-wire, fin-stabilized darts. Upon detonation the darts, or flechettes, are sprayed radially from the point of detonation, normally within sixty feet of the ground. It is extremely effective against personnel in the open or in dense foliage.
Shaped Charge
The discovery of what is variously referred to as the shaped charge effect, the hollow charge effect, the cavity effect, or the Munroe effect, dates back to the 1880s in this country. Dr. Charles Munroe, while working at the Naval Torpedo Station at Newport, Rhode Island, in the 1880s, discovered that if a block of guncotton with letters countersunk into its surface was det-onated with its lettered surface against a steel plate, the let-ters were indented into the surface of the steel. The essential features of this effect were also observed in about 1880 in both Germany and Norway, although no great use was made of it, and it was temporarily forgotten.
A shaped charge warhead consists basically of a hollow liner of metal material, usually copper or aluminum of conical, hemispherical, or other shape, backed on the convex side by explosive. A container, fuze, and detonating device are included.
When this warhead strikes a target, the fuze detonates the charge from the rear. A detonation wave sweeps forward and begins to collapse the metal cone liner at its apex. The collapse of the cone results in the formation and ejection of a continuous high-velocity molten jet of liner material. Velocity of the tip of the jet is on order of 8,500 meters per sec, while the trail-ing end of the jet has a velocity on the order of 1,500 meters per sec. This produces a velocity gradient that tends to stretch out or lengthen the jet. The jet is then followed by a slug that consists of about 80% of the liner mass. The slug has a velocity on the order of 600 meters per sec.
When the jet strikes a target of armor plate or mild steel, pressures in the range of hundreds of kilobars are produced at the point of contact. This pressure produces stresses far above the yield strength of steel, and the target material flows like a fluid out of the path of the jet. This phenomenon is called hydrodynamic penetration. There is so much radial momentum associated with the flow that the difference in diameter between the jet and the hole it produces depends on the characteristics of the target material. A larger diameter hole will be made in mild steel than in armor plate because the density and hardness of armor plate is greater. The depth of penetration into a very thick slab of mild steel will also be greater than that into homogeneous armor.
In general, the depth of penetration depends upon five factors:
Length of jet
Density of the target material
Hardness of target material
Density of the jet
Jet precision (straight vs. divergent)
The longer the jet, the greater the depth of penetration. Therefore, the greater the standoff distance (distance from target to base of cone) the better. This is true up to the point at which the jet particulates or breaks up (at 6 to 8 cone diameters from the cone base). Particulation is a result of the velocity gradient in the jet, which stretches it out until it breaks up. Jet precision refers to the straightness of the jet. If the jet is formed with some oscillation or wavy motion, then depth of penetration will be reduced. This is a function of the quality of the liner and the initial detonation location accuracy. The effectiveness of shaped charge warheads is reduced when they are caused to rotate. Spin-stabilized projectiles generally cannot use shaped-charge warheads.
Pyrotechnics
Pyrotechnics are typically employed for signaling, illuminating, or marking targets.
Illumination--These warheads usually contain a flare or magnesium flare candle as the payload, which is expelled by a small charge and is parachuted to the ground. During its descent the flare is kindled. The illuminating warhead is thus of great usefulness during night attacks in pointing out enemy fortifications. Because these flares are difficult to extinguish if accidentally ignited, extreme caution in their handling is required.
Smoke--These munitions are used primarily to screen troop movements and play a vital role in battlefield tactics. A black powder charge ignites and expels canisters that may be designed to emit white, yellow, red, green, or violet smoke.
Markers--White phosphorus is commonly employed as a pay-load to mark the position of the enemy. It can be very dangerous, especially in heavy concentrations. The material can self-ignite in air, cannot be extinguished by water, and will rekindle upon subsequent exposure to air. Body contact can produce serious burns. Copper sulphate prevents its re-ignition.
Cluster
Cluster munitions are canisters containing dozens or hundreds of small bomblets for use against a variety of targets, such as personnel, armored ve-hicles, or ships. Once in the air, the canisters open, spreading the bomblets out in a wide pattern. The advantage of this type of warhead is that it gives a wide area of coverage, which allows for a greater margin of error in delivery.
Flechettes
Flechettes are fin stabilized steel projectiles similar in appearance to arrows. During the Korean War the Chinese army tactic of human wave attacks against US lines of defence prompted interest in flechette projectiles in single and multiple projectile systems for small arms and antipersonnel (APERS) use. Flechettes have a performance criteria very different from the conventional rifle bullet. Typical modern flechettes are small light weight steel projectiles, and the velocity lost to air resistance is generally 375 fps. per 100 Meters of flight. Unlike rifle bullets, flechettes are not spin stabilized, but use fins to achieve level flight. The flechette's long body looses rigidity on target impact and bends into a hook, often breaking off the fin portion creating an additional wound. Flechette munitions include projectiles for use in the M16 rifle, CAWS (close assault weapons system), and 12 gage shotgun, as well as the 105mm M101A1/M102 howitzer, 2.75 in. FFAR (folding fin aircraft rocket), and the 70mm Hydra-70 FFAR.
Painting and marking
All projectiles are painted, both as a means of ready identification and as a rust preventative. The basic colors used for many years were olive drab (OD) for high-explosive rounds, gray for chemical rounds, blue for practice rounds, and black for drill rounds. A system of contrasting color markings or bands in addition to the basic color has also been used to identify the particular type of high explosive or chemical used as a filler. Color coding of recently produced projectiles is somewhat different. For example, illuminating and smoke rounds are no longer painted gray, the basic color for chemical shells. Illuminating rounds are now painted basically white or olive drab, and the smoke rounds are painted green. The basic color for dummy ammunition has been changed to bronze. Projectiles containing high explosive TNT Amatol, etc.) are painted yellow. Projectiles containing chemicals (gas or smoke) are painted blue-gray. Projectiles containing low explosives (black powder) are painted red. Projectiles are also stenciled to show the caliber, type of cannon used in, ammunition lot number, kind of filling, etc
Bullets For Beginners
Bullets for Beginners
Guns are generally classified according to use, size, and tradition. This varies among the military services. The basic distinction is between small arms and artillery. Any gun below a 20-millimeter bore size is generally classified as a small arm. An alternative term gaining increasing currency is "light arms," to include individual and light support weapons. The soldier's individual weapons consist in most countries of an assault rifle in caliber 5.56 or 7.62 mm. Light support weapons consist of machine guns, single shot grenade launchers and automatic grenade launchers. Machine guns are available in caliber 5.45, 5.56, 7.62, 12.7 and 14.5 mm. Single shot grenade launchers have a caliber of 40 mm, and generally fire a HE (high explosive) grenade out to a maximum range of about 400 meters. Automatic grenade launchers have a caliber of 30 or 40 mm, firing ammunition is of a HE (high explosive) or a HEDP (high explosive dual-purpose) type with a maximum range amounts to 2200 meters.
Pistol - A pistol is a hand-operated firearm having a chamber integral with or permanently aligned with the bore.
Revolver - A revolver is a hand-operated firearm with a revolving cylinder containing chambers for individual cartridges.
Rifle - A rifle is a shoulder firearm which can discharge a bullet through a rifled barrel 16 inches or longer. The spiral parallel grooves in the bore impart spin in the projectile, providing stability and extended range. Carbine - A carbine has a barrel under 16 inches in length, and is typically used by cavalry, artillery, engineers or others who require a weapon for self-defense and emergencies. Accuracy and ballistics tend to be inferior to the full version of the rifles they are adapted from.
Assault Rifle - rifles capable of single shot or automatic fire using a short cartridge providing accurate fire and more controllable recoil force than a standard rifle cartridge. By reducing the cartridge case and propellant, the cartridges weigh less and soldiers can carry more. These shorter rifles were developed in response to the recognition that most fire-fights take place at ranges under 400 yards. The small size of the assault rifle and its ability to fire at up to 800 rounds per minute has led to it being adopted by various forces as a replacement for the submachine gun.
Machine Pistol - A machine pistol is a firearm originally designed to fire, or capable of being fired, fully automatically by a single pull of the trigger.
Submachine Gun - lightweight one-man weapons capable of automatic fire, firing a low-powered pistol cartridge with limited range and accuracy.
Machine Gun - A general purpose machine gun functions as either a squad light automatic weapon [light machine gun] when mounted on a bipod and fired from the shoulder, or as a sustained fire long-range weapon [heavy machine gun] when mounted on a tripod or light vehicle and provided with an optical sight.
Bullets can be optimized for minimum time of flight, minimum dispersion, maximum retained kinetic energy, minimum cross wind sensitivity, minimum ballistic drop, maximum penetration, and limiting maximum range. For instance, a heavier bullet launched at lower muzzle velocity is a bullet designed to minimize cross wind sensitivity. As the bullet gets heavier, more of the projectile body can be dedicated to ogive length, reducing drag. Heavier, faster, lower drag is generally better, but with a fixed case volume, it is not possible to improve all of these attributes simultaneously. A bullet optimized for one parameter is often the worst solution for another important parameter. Optimizing one parameter requires compromise on others.
Small arms and machine-gun projectiles are made of solid metal; however, projectiles of 20-mm guns and larger have many components. The form of the forward end of the projectile is an ogival curve (generated by revolving an arc of a circle about a chord) that is aerodynamically efficient. Behind the ogive, the projectile is cylindrical with the exception of the bourrelet, which is slightly larger than the diameter of the body to reduce the surface area (and thus the friction) of the projectile contacting the gun bore. Near the after end of the projectile is the rotating band, which is actually larger than gun bore diameter to engage the rifling grooves and seal the bore while supporting the aft end of the projectile. The rifling actually engraves the rotating band to ensure a gas-tight seal. Aft of the rotating band the cylindrical shape may continue to the base of the projectile or it may be tapered to a "boat tail."
A complete round of small-arms ammunition is known as a cartridge, and is made up of the following components:
Bullet: The bullet in general is cylindrical. The nose may be round, as in the cal, .50 bullet, or ogival as in all service rifles and machine gun bullets. The base may be square or boattailed.
Types include the following:
o Armor-piercing bullets contain a core of hardened steel.
o Ball usually contain a slug of antimony hardened lead except in case of the cal, .50, wherein the outer core is of soft steel.
o Tracer contains a lead slug, and a chemical composition in the rear.
o Incendiary bullets contain an incendiary composition.
Cartridge case: The cartridge case is the means whereby the other components are assembled into the unit. It also provides a waterproof container for the propelling charge.
Primer: Percussion
Propelling charge: The propelling charge consists of a quanity of smokeless powder. The weight of the charge is not constant. It is adjusted for each powder lot to give the required velocity with pressure within the limits prescribed for the weapon in which it is fired.
NATO Standard Ammunition
Small Caliber ammunition types are differentiated by projectile tip identification paint, i.e., tracers are painted red or orange, armor piercing are black, dim trace are purple, etc.
Guns are generally classified according to use, size, and tradition. This varies among the military services. The basic distinction is between small arms and artillery. Any gun below a 20-millimeter bore size is generally classified as a small arm. An alternative term gaining increasing currency is "light arms," to include individual and light support weapons. The soldier's individual weapons consist in most countries of an assault rifle in caliber 5.56 or 7.62 mm. Light support weapons consist of machine guns, single shot grenade launchers and automatic grenade launchers. Machine guns are available in caliber 5.45, 5.56, 7.62, 12.7 and 14.5 mm. Single shot grenade launchers have a caliber of 40 mm, and generally fire a HE (high explosive) grenade out to a maximum range of about 400 meters. Automatic grenade launchers have a caliber of 30 or 40 mm, firing ammunition is of a HE (high explosive) or a HEDP (high explosive dual-purpose) type with a maximum range amounts to 2200 meters.
Pistol - A pistol is a hand-operated firearm having a chamber integral with or permanently aligned with the bore.
Revolver - A revolver is a hand-operated firearm with a revolving cylinder containing chambers for individual cartridges.
Rifle - A rifle is a shoulder firearm which can discharge a bullet through a rifled barrel 16 inches or longer. The spiral parallel grooves in the bore impart spin in the projectile, providing stability and extended range. Carbine - A carbine has a barrel under 16 inches in length, and is typically used by cavalry, artillery, engineers or others who require a weapon for self-defense and emergencies. Accuracy and ballistics tend to be inferior to the full version of the rifles they are adapted from.
Assault Rifle - rifles capable of single shot or automatic fire using a short cartridge providing accurate fire and more controllable recoil force than a standard rifle cartridge. By reducing the cartridge case and propellant, the cartridges weigh less and soldiers can carry more. These shorter rifles were developed in response to the recognition that most fire-fights take place at ranges under 400 yards. The small size of the assault rifle and its ability to fire at up to 800 rounds per minute has led to it being adopted by various forces as a replacement for the submachine gun.
Machine Pistol - A machine pistol is a firearm originally designed to fire, or capable of being fired, fully automatically by a single pull of the trigger.
Submachine Gun - lightweight one-man weapons capable of automatic fire, firing a low-powered pistol cartridge with limited range and accuracy.
Machine Gun - A general purpose machine gun functions as either a squad light automatic weapon [light machine gun] when mounted on a bipod and fired from the shoulder, or as a sustained fire long-range weapon [heavy machine gun] when mounted on a tripod or light vehicle and provided with an optical sight.
Bullets can be optimized for minimum time of flight, minimum dispersion, maximum retained kinetic energy, minimum cross wind sensitivity, minimum ballistic drop, maximum penetration, and limiting maximum range. For instance, a heavier bullet launched at lower muzzle velocity is a bullet designed to minimize cross wind sensitivity. As the bullet gets heavier, more of the projectile body can be dedicated to ogive length, reducing drag. Heavier, faster, lower drag is generally better, but with a fixed case volume, it is not possible to improve all of these attributes simultaneously. A bullet optimized for one parameter is often the worst solution for another important parameter. Optimizing one parameter requires compromise on others.
Small arms and machine-gun projectiles are made of solid metal; however, projectiles of 20-mm guns and larger have many components. The form of the forward end of the projectile is an ogival curve (generated by revolving an arc of a circle about a chord) that is aerodynamically efficient. Behind the ogive, the projectile is cylindrical with the exception of the bourrelet, which is slightly larger than the diameter of the body to reduce the surface area (and thus the friction) of the projectile contacting the gun bore. Near the after end of the projectile is the rotating band, which is actually larger than gun bore diameter to engage the rifling grooves and seal the bore while supporting the aft end of the projectile. The rifling actually engraves the rotating band to ensure a gas-tight seal. Aft of the rotating band the cylindrical shape may continue to the base of the projectile or it may be tapered to a "boat tail."
A complete round of small-arms ammunition is known as a cartridge, and is made up of the following components:
Bullet: The bullet in general is cylindrical. The nose may be round, as in the cal, .50 bullet, or ogival as in all service rifles and machine gun bullets. The base may be square or boattailed.
Types include the following:
o Armor-piercing bullets contain a core of hardened steel.
o Ball usually contain a slug of antimony hardened lead except in case of the cal, .50, wherein the outer core is of soft steel.
o Tracer contains a lead slug, and a chemical composition in the rear.
o Incendiary bullets contain an incendiary composition.
Cartridge case: The cartridge case is the means whereby the other components are assembled into the unit. It also provides a waterproof container for the propelling charge.
Primer: Percussion
Propelling charge: The propelling charge consists of a quanity of smokeless powder. The weight of the charge is not constant. It is adjusted for each powder lot to give the required velocity with pressure within the limits prescribed for the weapon in which it is fired.
NATO Standard Ammunition
Small Caliber ammunition types are differentiated by projectile tip identification paint, i.e., tracers are painted red or orange, armor piercing are black, dim trace are purple, etc.
Rebuilding .45 M1911A1 Pistol to USAMTU Specifications
U.S. Army Marksmanship Training Unit Standards & Procedures
- Rebuilding .45 M1911A1 Pistol to USAMTU Specifications -
1. The pistol will be set up and held in a recoiling type test cradle or machine rest, such as the Heg Rest or equivalent.
2. Test ammunition shall be caliber .45 Match hard ball or wadcutter as appropriate. Average extreme spread for three consecutive groups of ten rounds each are not to exceed 2.5 inches with no group larger than 3 inches for wadcutter pistols and 3 inches average for hard ball. No hardball group may exceed 3.5 inches.
3. Fitting the slide to the receiver
a. Select a slide which fits as closely as possible on the receiver, having a minimum of horizontal or vertical movement on the receiver.
b. Relieve the outer edges of the rails on the receiver to remove all phosphate finish from the bearing surfaces.
c. The slide is now ready for initial fitting to the receiver.
d. Place the slide (with the muzzle end upright) into a smooth jawed vise approximately 3 inches from the muzzle end (meaning the three inches of the slide aft of the muzzle are above the vise jaws). The top of the slide should be extended out from the left side of the vise so that the vise is gripping near the slide's rails.
e. Gently squeeze in steps of 1 inch at a time, for the complete length of the slide. Take extreme care not to squeeze excessively. The desired fit is a snug fit and yet the slide should be capable of being moved on the receiver by hand. Note that the slide may be squeezed much harder at the rear of the slide without crushing (because this area is the beefed up section of the slide!).
f. After the squeezing is completed, apply lapping compound (GK-7A) to the slide. Slip the slide onto the receiver while the receiver is correctly held and supported in the vise. Work the slide back and forth until the slide moves freely without binding on the receiver's rails. Wash out the compound with solvent (or Gun Scrubber, etc.), replace the slide on the receiver and check for movement by placing the slide into the firing position. The movement check is made by grasping the muzzle end of the slide in one hand and the receiver in the other hand. Then move each part in opposite directions and check for any HORIZONTAL movement.
g. If any horizontal movement is detected, repeat steps 3a through 3f as many times as necessary until there is no perceptible horizontal movement.
h. After all horizontal movement is eliminated, the slide is then ready for vertical fitting. With the slide in the firing position (also called the "battery" position), grasp the muzzle end of the slide and determine the amount of vertical movement.
i. Remove the slide and insert a parallel bar for swaging the receiver rails. Normally a bar 0.1170 inches thick is a good one to start with. A set of ten bars is needed, graduating from 0.1100 inches thick to 0.1200 inches, 5 inches long and 3/4 inches wide.
j. Using a 4 ounce ball peen hammer, swage the receiver's rails. The recommended technique for swaging is to hold the bar snugly and straight against the channel surface of the receiver and then use a highly polished hammer which has had the edges of the head broken lightly. Use an overlapping stroke with the hammer face being held as nearly parallel to the rail's surface as possible. The rails must be swaged as smoothly and as evenly as possible.
k. When both rails are indicating an even fit on the parallel bar, again relieve the edges of the rails to remove any high spots. Use GK-7A for lapping the slide to the receiver.
l. After lapping, recheck for VERTICAL movement. If any vertical movement still exists, repeat the swaging with the next smaller (thinner) parallel bar. Continue the swaging process until no perceptible vertical movement is noted.
m. Lap the slide and receiver until the slide will move under its own weight when the receiver is tilted and also no loose play (either horizontal or vertical) is noted.
n. Polish all work surfaces to remove all hammer strike marks or file marks or other blemishes.
o. Check the fit most carefully as this fit is the foundation of the entire operation. Repeat any of the earlier steps if a perfect fit is not achieved.
4. Fitting the barrel to the barrel bushing
a. Get an arbor that will hold an oversized bushing and set up the arbor between centers on a lathe. Turn to achieve a good fit. The nominal outside diameter is 0.7020 inches. While turning the bushing, be careful not to deform the retaining lug.
b. Measure the barrel diameter at the muzzle end. Install a precision reamer in the lathe and ream the inside of the bushing to the exact size of the muzzle end of the barrel. This should be 0.5790 inches.
c. With a high speed hand grinder, grind a slight radius in the bushing to allow the barrel to swivel slightly. This permits the barrel to enter the locking lugs of the slide without any binding. Take extreme care when grinding the inside radius so you do not remove any metal from the center of the bushing as this is an important fit (actually, it is the most important fit!) and must be precision ground. The barrel must slide back and forth in the bushing without any horizontal or vertical play.
d. The bushing should be a press fit and should require the use of a barrel bushing wrench to install or remove it from the slide.
5. Fitting an oversized barrel to the slide.
a. Insert a new oversized barrel into the slide and move it as far to the rear of the slide as possible. Observe the amount of steel to be removed from the barrel's tang in order to achieve the desired fit of the barrel hood and lugs into the battery position (firing position) of the slide. A layout die is recommended to fit the tang squarely to the slide.
b. The tang must be cut in a manner to maintain the original 90ø angles in order to match the slide locking recess. This is to insure that the barrel tang will enter the locking recess of the slide without binding the tang or locking lugs as the barrel locks up into the firing position.
c. When the tang is fitted to the recess in the slide, start to remove metal from the flat surface of the tang in order to fit the hood and lugs into the slide. Care must be taken not to remove too much metal. This fit should be as tight as possible in order to assure that a good fit will occur when the slide and barrel are in the firing position. A layout die is recommended to fit the tang squarely to the slide.
d. After the fitting has been made, use an alignment gauge 8" x 0.4375" with a 3/32" x «" tip inserted with the small tip to the rear of the slide in order to check alignment of the barrel with the firing pin. If the barrel is perfectly aligned, the small end of the tip will enter the firing pin aperture center and assure a center strike of the firing pin on the cartridge primer. If the barrel locks in the slide too high for the gauge tip to enter the firing pin aperture, it will be necessary to weld an appropriate thickness of metal into the slide above the barrel in order to get the proper alignment of the firing pin and barrel.
e. With a new barrel and bushing fit into the slide, place the slide with the barrel installed onto the receiver, making certain that the locking lugs on the bottom of the barrel fit into the recesses of the receiver without binding on any side. If there is rubbing on either side, make the necessary adjustments to assure a loose fit in the locking log recesses. At this point there must be a snug fit in the barrel tang and hood. A snug fit should also exist between the barrel bushing and slide as well as the barrel bushing and barrel.
f. Use a lug cutter, such as is available from Brownell's, to cut the locking lugs. The lugs must ride smoothly onto the slide stop pin, with the slide stop pin holding the barrel snugly against the top of the slide when the barrel and slide are in the firing position. After a tight fit has been achieved, polish the locking lugs with a high speed grinder and suitable rubberized abrasive tips. A Dremel tool works adequately. Take extreme care during the polishing to not polish on one side more than on the other. The lugs must be kept perfectly level. Frequent checks should be made using Dykem Blue on the lugs to assure perfect fit on the slide stop pin. Continue polishing until lockup is smooth but snug and resting equally on both sides of the lugs. At this point if the barrel hood and tang are too tight, remove a small amount of metal from the tang with a very light cut in order to permit a smooth lockup. It is good practice to use lapping compound to get a perfect fit.
g. After this fit is obtained, check the feed ramp on the barrel to be certain that the feed ramp on the barrel is forward of the feed ramp on the frame by approximately 1/32". This will insure that the nose of the cartridge will not hang up as the cartridge is loaded into the chamber from the magazine. Keep the angle on the barrel feed ramp the same as the ramp on the receiver (approximately 33ø). The barrel feed ramp includes approximately the lower diameter of barrel ground on the lower half of chamber end. The feed ramp on the barrel must not overhang the ramp on the receiver. However, the feed ramp on the barrel may be set forward of the feed ramp on the receiver as much as 3/32". The two feed ramps may be checked by locking the slide to the rear and looking through the ejection port.
6. Fitting the trigger
a. There are two types of triggers used on the U.S. Army's National Match .45 pistols: the standard Colt steel trigger and the aluminum National Match trigger found on the Gold Cup. Each trigger comes in two different length (long and short). The aluminum long trigger is slightly shorter than the long Colt trigger.
b. Using a number 36 drill, drill a hole in the trigger for the set screw. This hole will be tapped with a 6/32 tap. After tapping the hole, install a 6-32 x " Allen head set screw for the trigger stop screw. After completing this operation, check the trigger in the trigger opening of the receiver. Since most triggers are oversized in their width dimension, it is necessary to remove metal from each side of the trigger until the trigger will fit into the receiver without horizontal or vertical movement. When this fit is achieved, the next step is the trigger job, which includes fitting the sear and hammer.
7. Sear and hammer fitting
a. It is critically important that all original angles be maintained on the hammer and sear. The hammer hooks are then cut down to 0.0200" by using a thickness gauge. Placing the thickness gauge squarely on the hammer, file the hammer hooks down to 0.0200" using a smooth mill file.
b. Check the sear and hammer for proper engagement and proper angles using a hammer and sear mating fixture.
c. Polish the sides of the new National Match sear so they are smooth. Be sure the sear's sides are free of burrs or rough tool marks. Also polish the disconnector and trigger yoke (bow) to assure smooth operation when the pistol is reassembled and the moving parts are under normal working pressure.
d. The half cock notch is cut on each side of the hammer an even amount, so as to leave the hammer notch 0.1250" wide and then the depth of the sides of the half cock notch are cut down to the base of the hammer using a smooth mill file. This leaves the full half cock notch to catch the sear in the event the hammer falls. This provides complete safety on the same principle as is produced in the Colt factory for the .45 Gold Cup.
8. Trigger pull
a. Assemble the hammer, sear, disconnector and sear spring. Check for the desired break and weight of trigger pull. The trigger pull may be lightened by honing a slight radius on the point of the sear. To make a heavier pull, increase the engagement of the sear by increasing the angle on the point of the sear.
b. After proper operation and trigger pull have been obtained, adjust the trigger stop to have approximately 1/8" travel after the break. This is necessary to obtain the tolerances needed for the disconnector to work after each shot is fired.
c. Insure that the weight of the trigger pull is within the limits prescribed by N.R.A. rules and regulations and still maintain the required safety factors. The weight of trigger pull varies with each type of pistol used. Minimum recommended weights are as follows:
i. .45 ACP 230 FMJ (ball) 4 lbs. minimum
ii. .45 ACP wadcutter 3 lbs. minimum
iii. .38 Super 2 lbs. minimum
9. Sights
a. Sights used on .45 and .38 Super target pistols are the micrometer adjustable style. The Bo-Mar sight system is recommended due to its durability and precise movement. The point of impact may be moved as little as ¬" on the target. Install the sights according to the manufacturer's instructions and make certain the N.R.A. specifications are meet for competition pistols. Rules vary from time to time and the latest copy of the N.R.A. rules should be consulted.
10. Common malfunctions
a. Failure to feed properly.
i. In most cases the cartridge will nose upward against the top of the barrel hood and chamber. This can be caused by the feed ramp on the barrel having less than the necessary angle or the feed ramp on the barrel overhanging the feed ramp on the receiver. To correction this problem, grind the feed ramp on the barrel to a more forward angle and make sure the barrel does not overhang the feed ramp on the receiver. Polish all surfaces in order to remove all tool marks.
ii. Very frequently the magazine follower is bent to an improper angle or else the lips of the magazine may be too tight. This prevents the magazine from releasing the cartridge in time to allow the round to enter the chamber. If the cartridge noses UP, bend the follower DOWN. The correct angle should be 70ø to 75ø.
b. Failure to chamber the round.
i. This is characterized by the slide stopping 1/8" to 1/4" out of the full closed, battery position. Correct this problem by relieving the tension on the extractor and/or rounding off the bottom of the extractor to permit the extractor to cam itself onto the base of the cartridge with greater ease.
c. Cartridge "stove pipes" during ejection.
i. This malfunction is usually caused by the recoil spring being too strong (stiff) and not permitting the slide to go fully rearward, having the slide go fully rearward but coming forward too fast or because the ejector does not have a good square face. The recoil spring used for firing 230 grain ball/FMJ rounds normally has 29 to 33 coils. If you find it necessary to cut down the recoil spring, cut off only one coil (some prefer « coil) at a time until the problem is corrected.
ii. If the ejector is found to be round or worn, file the ejector's face square and maintain the original angles. Sometimes it is necessary to install a new ejector when the pistol is firing .45 wadcutters or .38 Super. This is because there are inadequate recoil forces to move the slide completely to the rear, permitting the cartridge case to exit the pistol in time.
d. Misfires.
i. First examine the detent made by the firing pin on the primer of the misfired cartridge. If the primer is not dented enough there could be a broken firing pin, burred firing pin or the firing pin could be binding in the firing pin retainer plate. Carefully check all of these points.
ii. It is possible to have a weak mainspring or the mainspring could be hanging up in the mainspring housing (due to a burr on the spring or in the housing itself). iii. Excessive headspace can cause misfires. Normal headspace is 0.0080" to 0.0120" and should NEVER exceed 0.0120". If the shooter is using his own reloads, examine his cases for proper length.
e. Pistol fires full automatic.
i. This can be caused by several things: improperly adjusted trigger stop (too close), too light a trigger pull, disconnector too short due to excessive wear or polishing or the center leaf of the sear spring is simply too weak.
ii. If the problem is traced to an improperly positioned trigger stop, readjust the trigger stop to permit not less than 1/8" travel after the break.
iii. Make sure the trigger pull is not less than the appropriate value specified in item 8c. Increase the trigger pull weight by increasing the engagement of the sear and hammer.
iv. If the problem is traced to the disconnector, simply replace it. Polish it before installation to remove and burrs.
v. If the center leaf of the sear spring has lost its temper and will not longer hold its set, replace the sear spring with a new one.
11. Differences between .45 ACP and .38 Super pistols.
a. While the pistols are generally built in the same manner, some differences do exist. The .38 Super has a recoil spring composed of softer 0.0330 spring wire.
b. The .38 Super extractor is specially designed and fitted to have less tension gripping the cartridge case.
c. The .38 Super extractor claw is deepened and shaped differently in order to cam onto the cartridge case.
d. The trigger pull on the .38 Super is set to 2« pounds.
e. Gold Cup type magazines are used in the .38 Super
- Rebuilding .45 M1911A1 Pistol to USAMTU Specifications -
1. The pistol will be set up and held in a recoiling type test cradle or machine rest, such as the Heg Rest or equivalent.
2. Test ammunition shall be caliber .45 Match hard ball or wadcutter as appropriate. Average extreme spread for three consecutive groups of ten rounds each are not to exceed 2.5 inches with no group larger than 3 inches for wadcutter pistols and 3 inches average for hard ball. No hardball group may exceed 3.5 inches.
3. Fitting the slide to the receiver
a. Select a slide which fits as closely as possible on the receiver, having a minimum of horizontal or vertical movement on the receiver.
b. Relieve the outer edges of the rails on the receiver to remove all phosphate finish from the bearing surfaces.
c. The slide is now ready for initial fitting to the receiver.
d. Place the slide (with the muzzle end upright) into a smooth jawed vise approximately 3 inches from the muzzle end (meaning the three inches of the slide aft of the muzzle are above the vise jaws). The top of the slide should be extended out from the left side of the vise so that the vise is gripping near the slide's rails.
e. Gently squeeze in steps of 1 inch at a time, for the complete length of the slide. Take extreme care not to squeeze excessively. The desired fit is a snug fit and yet the slide should be capable of being moved on the receiver by hand. Note that the slide may be squeezed much harder at the rear of the slide without crushing (because this area is the beefed up section of the slide!).
f. After the squeezing is completed, apply lapping compound (GK-7A) to the slide. Slip the slide onto the receiver while the receiver is correctly held and supported in the vise. Work the slide back and forth until the slide moves freely without binding on the receiver's rails. Wash out the compound with solvent (or Gun Scrubber, etc.), replace the slide on the receiver and check for movement by placing the slide into the firing position. The movement check is made by grasping the muzzle end of the slide in one hand and the receiver in the other hand. Then move each part in opposite directions and check for any HORIZONTAL movement.
g. If any horizontal movement is detected, repeat steps 3a through 3f as many times as necessary until there is no perceptible horizontal movement.
h. After all horizontal movement is eliminated, the slide is then ready for vertical fitting. With the slide in the firing position (also called the "battery" position), grasp the muzzle end of the slide and determine the amount of vertical movement.
i. Remove the slide and insert a parallel bar for swaging the receiver rails. Normally a bar 0.1170 inches thick is a good one to start with. A set of ten bars is needed, graduating from 0.1100 inches thick to 0.1200 inches, 5 inches long and 3/4 inches wide.
j. Using a 4 ounce ball peen hammer, swage the receiver's rails. The recommended technique for swaging is to hold the bar snugly and straight against the channel surface of the receiver and then use a highly polished hammer which has had the edges of the head broken lightly. Use an overlapping stroke with the hammer face being held as nearly parallel to the rail's surface as possible. The rails must be swaged as smoothly and as evenly as possible.
k. When both rails are indicating an even fit on the parallel bar, again relieve the edges of the rails to remove any high spots. Use GK-7A for lapping the slide to the receiver.
l. After lapping, recheck for VERTICAL movement. If any vertical movement still exists, repeat the swaging with the next smaller (thinner) parallel bar. Continue the swaging process until no perceptible vertical movement is noted.
m. Lap the slide and receiver until the slide will move under its own weight when the receiver is tilted and also no loose play (either horizontal or vertical) is noted.
n. Polish all work surfaces to remove all hammer strike marks or file marks or other blemishes.
o. Check the fit most carefully as this fit is the foundation of the entire operation. Repeat any of the earlier steps if a perfect fit is not achieved.
4. Fitting the barrel to the barrel bushing
a. Get an arbor that will hold an oversized bushing and set up the arbor between centers on a lathe. Turn to achieve a good fit. The nominal outside diameter is 0.7020 inches. While turning the bushing, be careful not to deform the retaining lug.
b. Measure the barrel diameter at the muzzle end. Install a precision reamer in the lathe and ream the inside of the bushing to the exact size of the muzzle end of the barrel. This should be 0.5790 inches.
c. With a high speed hand grinder, grind a slight radius in the bushing to allow the barrel to swivel slightly. This permits the barrel to enter the locking lugs of the slide without any binding. Take extreme care when grinding the inside radius so you do not remove any metal from the center of the bushing as this is an important fit (actually, it is the most important fit!) and must be precision ground. The barrel must slide back and forth in the bushing without any horizontal or vertical play.
d. The bushing should be a press fit and should require the use of a barrel bushing wrench to install or remove it from the slide.
5. Fitting an oversized barrel to the slide.
a. Insert a new oversized barrel into the slide and move it as far to the rear of the slide as possible. Observe the amount of steel to be removed from the barrel's tang in order to achieve the desired fit of the barrel hood and lugs into the battery position (firing position) of the slide. A layout die is recommended to fit the tang squarely to the slide.
b. The tang must be cut in a manner to maintain the original 90ø angles in order to match the slide locking recess. This is to insure that the barrel tang will enter the locking recess of the slide without binding the tang or locking lugs as the barrel locks up into the firing position.
c. When the tang is fitted to the recess in the slide, start to remove metal from the flat surface of the tang in order to fit the hood and lugs into the slide. Care must be taken not to remove too much metal. This fit should be as tight as possible in order to assure that a good fit will occur when the slide and barrel are in the firing position. A layout die is recommended to fit the tang squarely to the slide.
d. After the fitting has been made, use an alignment gauge 8" x 0.4375" with a 3/32" x «" tip inserted with the small tip to the rear of the slide in order to check alignment of the barrel with the firing pin. If the barrel is perfectly aligned, the small end of the tip will enter the firing pin aperture center and assure a center strike of the firing pin on the cartridge primer. If the barrel locks in the slide too high for the gauge tip to enter the firing pin aperture, it will be necessary to weld an appropriate thickness of metal into the slide above the barrel in order to get the proper alignment of the firing pin and barrel.
e. With a new barrel and bushing fit into the slide, place the slide with the barrel installed onto the receiver, making certain that the locking lugs on the bottom of the barrel fit into the recesses of the receiver without binding on any side. If there is rubbing on either side, make the necessary adjustments to assure a loose fit in the locking log recesses. At this point there must be a snug fit in the barrel tang and hood. A snug fit should also exist between the barrel bushing and slide as well as the barrel bushing and barrel.
f. Use a lug cutter, such as is available from Brownell's, to cut the locking lugs. The lugs must ride smoothly onto the slide stop pin, with the slide stop pin holding the barrel snugly against the top of the slide when the barrel and slide are in the firing position. After a tight fit has been achieved, polish the locking lugs with a high speed grinder and suitable rubberized abrasive tips. A Dremel tool works adequately. Take extreme care during the polishing to not polish on one side more than on the other. The lugs must be kept perfectly level. Frequent checks should be made using Dykem Blue on the lugs to assure perfect fit on the slide stop pin. Continue polishing until lockup is smooth but snug and resting equally on both sides of the lugs. At this point if the barrel hood and tang are too tight, remove a small amount of metal from the tang with a very light cut in order to permit a smooth lockup. It is good practice to use lapping compound to get a perfect fit.
g. After this fit is obtained, check the feed ramp on the barrel to be certain that the feed ramp on the barrel is forward of the feed ramp on the frame by approximately 1/32". This will insure that the nose of the cartridge will not hang up as the cartridge is loaded into the chamber from the magazine. Keep the angle on the barrel feed ramp the same as the ramp on the receiver (approximately 33ø). The barrel feed ramp includes approximately the lower diameter of barrel ground on the lower half of chamber end. The feed ramp on the barrel must not overhang the ramp on the receiver. However, the feed ramp on the barrel may be set forward of the feed ramp on the receiver as much as 3/32". The two feed ramps may be checked by locking the slide to the rear and looking through the ejection port.
6. Fitting the trigger
a. There are two types of triggers used on the U.S. Army's National Match .45 pistols: the standard Colt steel trigger and the aluminum National Match trigger found on the Gold Cup. Each trigger comes in two different length (long and short). The aluminum long trigger is slightly shorter than the long Colt trigger.
b. Using a number 36 drill, drill a hole in the trigger for the set screw. This hole will be tapped with a 6/32 tap. After tapping the hole, install a 6-32 x " Allen head set screw for the trigger stop screw. After completing this operation, check the trigger in the trigger opening of the receiver. Since most triggers are oversized in their width dimension, it is necessary to remove metal from each side of the trigger until the trigger will fit into the receiver without horizontal or vertical movement. When this fit is achieved, the next step is the trigger job, which includes fitting the sear and hammer.
7. Sear and hammer fitting
a. It is critically important that all original angles be maintained on the hammer and sear. The hammer hooks are then cut down to 0.0200" by using a thickness gauge. Placing the thickness gauge squarely on the hammer, file the hammer hooks down to 0.0200" using a smooth mill file.
b. Check the sear and hammer for proper engagement and proper angles using a hammer and sear mating fixture.
c. Polish the sides of the new National Match sear so they are smooth. Be sure the sear's sides are free of burrs or rough tool marks. Also polish the disconnector and trigger yoke (bow) to assure smooth operation when the pistol is reassembled and the moving parts are under normal working pressure.
d. The half cock notch is cut on each side of the hammer an even amount, so as to leave the hammer notch 0.1250" wide and then the depth of the sides of the half cock notch are cut down to the base of the hammer using a smooth mill file. This leaves the full half cock notch to catch the sear in the event the hammer falls. This provides complete safety on the same principle as is produced in the Colt factory for the .45 Gold Cup.
8. Trigger pull
a. Assemble the hammer, sear, disconnector and sear spring. Check for the desired break and weight of trigger pull. The trigger pull may be lightened by honing a slight radius on the point of the sear. To make a heavier pull, increase the engagement of the sear by increasing the angle on the point of the sear.
b. After proper operation and trigger pull have been obtained, adjust the trigger stop to have approximately 1/8" travel after the break. This is necessary to obtain the tolerances needed for the disconnector to work after each shot is fired.
c. Insure that the weight of the trigger pull is within the limits prescribed by N.R.A. rules and regulations and still maintain the required safety factors. The weight of trigger pull varies with each type of pistol used. Minimum recommended weights are as follows:
i. .45 ACP 230 FMJ (ball) 4 lbs. minimum
ii. .45 ACP wadcutter 3 lbs. minimum
iii. .38 Super 2 lbs. minimum
9. Sights
a. Sights used on .45 and .38 Super target pistols are the micrometer adjustable style. The Bo-Mar sight system is recommended due to its durability and precise movement. The point of impact may be moved as little as ¬" on the target. Install the sights according to the manufacturer's instructions and make certain the N.R.A. specifications are meet for competition pistols. Rules vary from time to time and the latest copy of the N.R.A. rules should be consulted.
10. Common malfunctions
a. Failure to feed properly.
i. In most cases the cartridge will nose upward against the top of the barrel hood and chamber. This can be caused by the feed ramp on the barrel having less than the necessary angle or the feed ramp on the barrel overhanging the feed ramp on the receiver. To correction this problem, grind the feed ramp on the barrel to a more forward angle and make sure the barrel does not overhang the feed ramp on the receiver. Polish all surfaces in order to remove all tool marks.
ii. Very frequently the magazine follower is bent to an improper angle or else the lips of the magazine may be too tight. This prevents the magazine from releasing the cartridge in time to allow the round to enter the chamber. If the cartridge noses UP, bend the follower DOWN. The correct angle should be 70ø to 75ø.
b. Failure to chamber the round.
i. This is characterized by the slide stopping 1/8" to 1/4" out of the full closed, battery position. Correct this problem by relieving the tension on the extractor and/or rounding off the bottom of the extractor to permit the extractor to cam itself onto the base of the cartridge with greater ease.
c. Cartridge "stove pipes" during ejection.
i. This malfunction is usually caused by the recoil spring being too strong (stiff) and not permitting the slide to go fully rearward, having the slide go fully rearward but coming forward too fast or because the ejector does not have a good square face. The recoil spring used for firing 230 grain ball/FMJ rounds normally has 29 to 33 coils. If you find it necessary to cut down the recoil spring, cut off only one coil (some prefer « coil) at a time until the problem is corrected.
ii. If the ejector is found to be round or worn, file the ejector's face square and maintain the original angles. Sometimes it is necessary to install a new ejector when the pistol is firing .45 wadcutters or .38 Super. This is because there are inadequate recoil forces to move the slide completely to the rear, permitting the cartridge case to exit the pistol in time.
d. Misfires.
i. First examine the detent made by the firing pin on the primer of the misfired cartridge. If the primer is not dented enough there could be a broken firing pin, burred firing pin or the firing pin could be binding in the firing pin retainer plate. Carefully check all of these points.
ii. It is possible to have a weak mainspring or the mainspring could be hanging up in the mainspring housing (due to a burr on the spring or in the housing itself). iii. Excessive headspace can cause misfires. Normal headspace is 0.0080" to 0.0120" and should NEVER exceed 0.0120". If the shooter is using his own reloads, examine his cases for proper length.
e. Pistol fires full automatic.
i. This can be caused by several things: improperly adjusted trigger stop (too close), too light a trigger pull, disconnector too short due to excessive wear or polishing or the center leaf of the sear spring is simply too weak.
ii. If the problem is traced to an improperly positioned trigger stop, readjust the trigger stop to permit not less than 1/8" travel after the break.
iii. Make sure the trigger pull is not less than the appropriate value specified in item 8c. Increase the trigger pull weight by increasing the engagement of the sear and hammer.
iv. If the problem is traced to the disconnector, simply replace it. Polish it before installation to remove and burrs.
v. If the center leaf of the sear spring has lost its temper and will not longer hold its set, replace the sear spring with a new one.
11. Differences between .45 ACP and .38 Super pistols.
a. While the pistols are generally built in the same manner, some differences do exist. The .38 Super has a recoil spring composed of softer 0.0330 spring wire.
b. The .38 Super extractor is specially designed and fitted to have less tension gripping the cartridge case.
c. The .38 Super extractor claw is deepened and shaped differently in order to cam onto the cartridge case.
d. The trigger pull on the .38 Super is set to 2« pounds.
e. Gold Cup type magazines are used in the .38 Super
Pipe Pistol for .22 Caliber Ammunition
Pipe pistol for .22 caliber ammunition long or short cartrige
A .22 Caliber pistol can be made from 1/8 in. nominal diameter extra heavy, steel gas or water pipe and fittings. Lethal range is approximately 33 yards (30 meters).
MATERIAL REQUIRED:
Steel pipe, extra heavy, 1/8 in. (3 mm) nominal diameter and 6 in. (15 cm) long with threaded ends (nipple)
Solid pipe plug, 1/8 in. (3mm) nominal diameter
Metal strap, appriximately 1/8 in. X 1/4 in. X 5 in.(3 mm x 6 mm X 125 mm or 12-1/2 sm)
Elastic bands
Flat head nail - 6D or 8D ( approximately 1/16 in. (1-1/2 mm) diameter
2 Wood screws, #8
Hard wood, 8 in. X 5 in. X 1 in, (20 cm X 12-1/2 cm X 2-1/2 cm)
Drill
Wood or metal rod, 1/8 in. (3 mm) diameter and 8 in. (20 cm) long
Saw or knife
Procedure: **********
1. Carefully inspect pipe and fittings.
a. Make sure that there are No cracks or other flaws in the pipe or fittings. b. Check inside diameter of pipe using a .22 caliber cartridge, long or short, as a gauge. The buller should fit closely into the pipe witthout forcing, but the case SHOULD NOT fit into the pipe.
c. Outside diameter of pipe MUST NOT BE less than 1-1/2 times the bullet diameter.
2. Drill a 15/64 in. (1/2) diameter hole 9/16 in. (1-1/2 cm) deep in pipe for long cartridgd. (If a short cartridge is used, drill hole 3/8 in. (1 cm) deep). When a cartridge is inserted into the pipe, the shoulder of the case should butt against the end of the pipe.
3. Screw the coupling onto the pipe. Cut coupling length to allow pipe to thread in pipe slush against the cartridge case.
4. Drill a hole off center of the pupe plug just large wnough for the nail to fit through.
NOTE: Drilled hole MUST BE OFF CENTER in plug.
5. Push nail through pupe plug until head of nail is flush with square end. Cut nail off at other end 1/16 in. (1-1/2 mm) away from plug. Round off end with file.
6. Bend metal strap to "U" shape and drill holes for wood screws. File two small notches at top.
7. Saw ot otherwise shape 1' (2.54 cm) thick hard wood into stock.
8. Drill a 9/16" diamter (1.43 cm) hole through the stock. The center of the hole should be approximately 1/2" (1.27 cm) from the top.
9. Slide the pipe through this hole and attach front coupling.
NOTE: If 9/16" drill is not available cut a "V" groove in the top of the stock and tape pipe securely in place.
10. Position metal strap on stock so that top will hit the head of the nail. Attach to stock with wood screw on each side.
11. String elastic bands from front coupling to notch on each side of the strap.
SAFTY CHECK - TEST FIRE PISTOL BEFORE HAND FIRING
1. Locate a barrier such as a stone wall or large tree which you can stand behind in case the pistol ruptures when fired.
2. Mount pistol solidly to a table or other rigid support at least ten feet in front of the barrier.
3. Attach a cord to the firing strap on the pistol.
4. Holding the other end of the cord, go behind the barrier.
5. Pull the cord so that the firing strap is held back.
6. Release the cord to fire the pistol. (If pistol does not fire, shorten the elastic bands or increase their number.)
IMPORTANT- Fire at least five rounds from behind varruer and then re-inspect the pistol before you attempt to hand fire it.
HOW TO OPERATE PISTOL
1. To Load
a. Remove plug from rear coupling.
b. Place cartridge into pipe.
c. Replace plug.
2. TO FIRE
a. Pull strap back and hold with thunb until ready.
b. Release strap.
3. TO REMOVE SHELL CASE
a. Remove plug from rear coupling.
b. Insert 1/4' diameter steel or wooden rod into front of pistol and push shell case out.
A .22 Caliber pistol can be made from 1/8 in. nominal diameter extra heavy, steel gas or water pipe and fittings. Lethal range is approximately 33 yards (30 meters).
MATERIAL REQUIRED:
Steel pipe, extra heavy, 1/8 in. (3 mm) nominal diameter and 6 in. (15 cm) long with threaded ends (nipple)
Solid pipe plug, 1/8 in. (3mm) nominal diameter
Metal strap, appriximately 1/8 in. X 1/4 in. X 5 in.(3 mm x 6 mm X 125 mm or 12-1/2 sm)
Elastic bands
Flat head nail - 6D or 8D ( approximately 1/16 in. (1-1/2 mm) diameter
2 Wood screws, #8
Hard wood, 8 in. X 5 in. X 1 in, (20 cm X 12-1/2 cm X 2-1/2 cm)
Drill
Wood or metal rod, 1/8 in. (3 mm) diameter and 8 in. (20 cm) long
Saw or knife
Procedure: **********
1. Carefully inspect pipe and fittings.
a. Make sure that there are No cracks or other flaws in the pipe or fittings. b. Check inside diameter of pipe using a .22 caliber cartridge, long or short, as a gauge. The buller should fit closely into the pipe witthout forcing, but the case SHOULD NOT fit into the pipe.
c. Outside diameter of pipe MUST NOT BE less than 1-1/2 times the bullet diameter.
2. Drill a 15/64 in. (1/2) diameter hole 9/16 in. (1-1/2 cm) deep in pipe for long cartridgd. (If a short cartridge is used, drill hole 3/8 in. (1 cm) deep). When a cartridge is inserted into the pipe, the shoulder of the case should butt against the end of the pipe.
3. Screw the coupling onto the pipe. Cut coupling length to allow pipe to thread in pipe slush against the cartridge case.
4. Drill a hole off center of the pupe plug just large wnough for the nail to fit through.
NOTE: Drilled hole MUST BE OFF CENTER in plug.
5. Push nail through pupe plug until head of nail is flush with square end. Cut nail off at other end 1/16 in. (1-1/2 mm) away from plug. Round off end with file.
6. Bend metal strap to "U" shape and drill holes for wood screws. File two small notches at top.
7. Saw ot otherwise shape 1' (2.54 cm) thick hard wood into stock.
8. Drill a 9/16" diamter (1.43 cm) hole through the stock. The center of the hole should be approximately 1/2" (1.27 cm) from the top.
9. Slide the pipe through this hole and attach front coupling.
NOTE: If 9/16" drill is not available cut a "V" groove in the top of the stock and tape pipe securely in place.
10. Position metal strap on stock so that top will hit the head of the nail. Attach to stock with wood screw on each side.
11. String elastic bands from front coupling to notch on each side of the strap.
SAFTY CHECK - TEST FIRE PISTOL BEFORE HAND FIRING
1. Locate a barrier such as a stone wall or large tree which you can stand behind in case the pistol ruptures when fired.
2. Mount pistol solidly to a table or other rigid support at least ten feet in front of the barrier.
3. Attach a cord to the firing strap on the pistol.
4. Holding the other end of the cord, go behind the barrier.
5. Pull the cord so that the firing strap is held back.
6. Release the cord to fire the pistol. (If pistol does not fire, shorten the elastic bands or increase their number.)
IMPORTANT- Fire at least five rounds from behind varruer and then re-inspect the pistol before you attempt to hand fire it.
HOW TO OPERATE PISTOL
1. To Load
a. Remove plug from rear coupling.
b. Place cartridge into pipe.
c. Replace plug.
2. TO FIRE
a. Pull strap back and hold with thunb until ready.
b. Release strap.
3. TO REMOVE SHELL CASE
a. Remove plug from rear coupling.
b. Insert 1/4' diameter steel or wooden rod into front of pistol and push shell case out.
The FBI's 10mm Pistol
by John C. Hall
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THE FBI'S 10MM PISTOL
By JOHN C. HALL
Special Agent/Unit Chief
Firearms Training Unit
FBI Academy
Quantico, VA
For several decades, FBI Agents carried the .38 caliber revolver as a standard firearm. Now, after extensive testing and evaluation, the FBI is converting to a new semiautomatic pistol. The new pistol, built to FBI specifications and chambered for a new cartridge; the 10mm, will be issued to all FBI Agents to replace existing revolvers. This article describes the process that led to this decision.
BACKGROUND
The authority for FBI Agents to carry firearms was first granted in 1934. Although pistols were sometimes issued or permitted on a limited basis, the revolver predominated as the FBI sidearm. The first significant shift occurred in 1981, when Special Weapons and Tactics (SWAT) teams were equipped with large capacity 9mm pistols. Since then, 9mm pistols have also become the issue weapons for the FBI's Hostage Rescue Team (HRT) and special surveillance teams.
For the general Agent population, however, revolvers remained the issue weapon, though the increasing use of pistols reflected a growing recognition that the modern pistol provides certain advantages over the revolver. Primarily, pistols are generally more compact and portable and provide a larger ammunition capacity. They are also quicker and easier to reload. Moreover, experience has shown that pistols are generally easier to shoot quickly and accurately due to the self©cocking operation of the slide following each shot and the more efficient transmission of recoil. What is most important, however, is that pistols have proven to be durable and reliable.
Undoubtedly, interest in pistols intensified when innovative designs of the weapon began to appear on the market during the early 1980s. Whereas the basic revolver design remains much as it was at the turn of the century, the pistol has been virtually refashioned in recent years, providing a wide range of such innovative features as double©stacked large capacity magazines, double©action triggers, ambidextrous controls, multiple safety devices, and endless varieties of shapes and sizes.
Meanwhile, other events entered into the picture. Instances where law enforcement officers were confronting more violent, heavily armed subjects appeared to be on the rise. Theincreasing use of semiautomatic and even fully automatic weapons by certain segments of the criminal element began to raise concerns about the adequacy of law enforcement armament.
SELECTION OF A NEW HANDGUN
In 1987, new impetus was given to the FBI's ongoing evaluation of firearms and ammunition. The Firearms Training Unit, located at the FBI Academy in Quantico, VA, set out to identify the best possible handgun for FBI Agents. Firearms training experts undertook a major testing project to evaluate a variety of 9mm and .45 caliber pistols then on the market. While several of the pistols tested were effective, none possessed all of the features desired in a general issue FBI weapon. The challenge was to dev elop a pistol that met the needs of the FBI. In the meantime, as a response to a growing perception within Agent ranks that a pistol was preferable to the revolver, the Director of the FBI authorized Agents to use personally owned pistols, either 9mm or .45 caliber, as long as the weapons were of approved manufacture and design and the training and qualification standards were met.
A Question of Caliber
The most critical, and controversial, issue relating to the selection of a new FBI handgun was that of caliber. Questions have been raised not only about the adequacy of some weapons but also about the wounding effectiveness of some ammunition. Case accounts of shootings document the fact that subjects receiving fatal, but not incapacitating, wounds have been able to return fire and inflict further damage.
Wound Ballistics
As a means of resolving the problem, the FBI convened a Wound Ballistics Seminar at the FBI Academy in September 1987. The participants included noted individuals from the scientific and medical communities from throughout the Nation who possessed relevant expertise in the field of wound ballistics. One of the primary purposes of the seminar was to identify the performance criteria of a bullet most likely to inflict an incapacitating wound on a human target.
A second purpose of the seminar was to determine, if possible, which of the two calibers, the 9mm or the .45, was likely to be most effective in accomplishing that goal. And, although the seminar was unsuccessful in conclusively resolving the caliber question, it did identify the desirable performance criteria of an effective bullet.
Incapacitation, in the law enforcement context, may be simply described as bringing about the immediate cessation of hostile or threatening activities. Incapacitation may result from psychological or physiological factors. Psychologically, some individuals are predisposed to fall down at the sound of gunfire, while others may continue to fight even though they are seriously-©even fatally-©wounded. Because a particular person's psychological response to a gunshot wound cannot be predicted, ammunition performance must be viewed from the perspective of physiological incapacitation.
The seminar participants unanimously concluded that physiological incapacitation can be accomplished in one of two ways©©damage to the central nervous system (the brain or upper spinal column) or significant loss of blood. Because the placement of a shot in the relatively small, highly mobile target area of the brain cannot be counted upon in an armed confrontation, a bullet must therefore be capable of penetrating the body sufficiently to pass through major arteries and blood- bearing organs to ensure timely physiological incapacitation. Without adequate penetration, physiological incapacitation cannot be attained. Given adequate penetration, the only reliable way to increase the effectiveness of the wound is to increase its size, thus increasing the amount of tissue damage and the rate of hemorrhage. Thus, the FBI's test program was designed to evaluate bullet penetration and wound size.
Ammunition Test Design
With the performance criteria acquired from the Wound Ballistics Seminar, the next step was to design and construct a series of ammunition tests to measure the performance of different rounds against those standards. For that purpose, the Firearms Training Unit established a working group which included personnel from the Special Operations and Research Unit, the Hostage Rescue Team, and the Institutional Research and Development Unit.
The tests were designed to simulate factors realistically. Therefore, if the effects of bullets upon human tissue were to be realistically measured, a substance that would duplicate human tissue was needed. Based upon the research of Dr. Martin Fackler, Director of the Army's Wound Ballistics Laboratory, at the Letterman Institute in San Francisco, 10% ballistic gelatin was selected to simulate soft human muscle tissue. Eight separate penetration tests were conducted by firing bullets into this substanc e.
Also, since experience demonstrated that bare tissue is seldom visible on a target in a violent confrontation, seven of the eight tests included covering the gelatin with typical clothing material (cotton T©shirt material, flannel shirt material, 10 oz. down in a nylon carrier, and denim). To assure validity and standardization, clothing manufacturers were consulted to determine the average thread count in typical underclothing, shirts, and jackets.
Other factors were then considered. Because FBI Agents frequently confront subjects in vehicles, behind doors or walls, and at various distances, clothed gelatin was placed behind windshield glass, car door metal, plaster board and plywood. Again, manufacturers in the construction and automobile industries were consulted to assure that the materials used replicated substances that bullets would have to pass through in real©life situations. While most of the test shots were fired from a distance of 10 feet, some of the tests were conducted at 20 yards to assess the effects of distance and velocity loss on penetration potent ial.
Five shots were fired in each of the 8 penetration tests, providing a total of 40 shots for each caliber or bullet type tested.
The Competing Calibers
Once the tests were designed, a decision had to be made regarding the calibers to be tested. In pistol cartridges, the two most obvious contenders were the 9mm and .45. The 9mm round tested was the 147 grain subsonic hollow point round produced by Winchester; the .45 round selected for the test was the Remington 185 grain hollow point. The selection of these particular cartridges for testing was based, in large part, on the consensus of the Wound Ballistic Workshop participants that these bullets should p rovide superior penetration over other hollow point bullets in their respective calibers.
In the meantime, a separate research and development project had been undertaken with the 10mm cartridge to assess its application to law enforcement work. Although the 10mm (.40 caliber) is a relatively new cartridge, with few weapons presently chambered for it, its unique position halfway in size between the 9mm (.35 caliber) and the .45 appeared to offer the possibility of a third viable law enforcement pistol cartridge. In addition, unlike its other competitors, the potential of the new cartridge was virtually untapped.
Samples of commercially available 10mm ammunition were acquired and preliminarily evaluated as to suitability for law enforcement use. The high chamber pressures generated by the commercial loadings, with the resultant heavy recoil and muzzle blast, tended to offset the otherwise excellent performance of the round. Therefore, the FBI Firearms Training Unit decided to create a new loading for the 10mm, one with velocities comparable to those of the competing 9mm and .45 cartridges. A 180 grain hollow poi nt bullet was acquired and handloaded to a velocity of 950 feet per second. This loading not only matched the velocities of the other two cartridges, but it also dramatically reduced recoil and muzzle blast.
In the absence of factory ammunition built to the desired specifications, the 10mm rounds initially subjected to the test protocol were those handloaded by the Firearms Training Unit staff. Subsequently, factory©loaded 10mm ammunition was acquired and built to the desired specifications, which actually met or surpassed the performance of the handloaded test ammunition.
The Test Procedures
Because the objective was to test ammunition and not weapons, the initial tests were conducted with industry standard test barrels. These barrels are built to standards established by the Sporting Arms and Ammunition Manufacturing Institute (SAAMI) and are tailored to optimize the ballistic efficiency of each caliber. Test barrel length is determined by the internal ballistics of the caliber. Consequently, the barrel lengths vary with each caliber. For example, the optimal test barrel for the 9mm is 4" i n length, while those of the 10mm and .45 are 6".
The immediate concern was the possibility that the longer test barrels for the 10mm and .45 would provide an advantage by increasing their velocities. In reality, it was discovered that increased velocity actually diminishes the penetration performance of hollow point bullets in gelatin by increasing the rate and degree of expansion. It was noted, for example, that both the 10mm and .45 achieved lower velocities, but greater penetration, when fired from shorter pistol barrels than when fired from the long er test barrels with somewhat higher velocities. Thus, the longer test barrels used with the 10mm and .45 worked as a handicap for those two calibers by lessening the degree of penetration. That handicap would have been eliminated by using test barrels of equal lengths, and the disparity between the penetration performance of the 9mm and the two other calibers would have been even greater than that actually attained. Since the longer test barrels were not giving any advantage to the 10mm and the .45 calib er (quite the contrary), the tests were continued with existing equipment.
After initial tests to measure velocity and accuracy, 40 rounds of each caliber were fired by FBI firearms personnel to measure penetration and wound volume. Following each shot, red dye was injected into the wound channel created by the passage of the bullet into the gelatin, and a photograph was taken. Then a separate team from the Institutional Research and Development Unit conducted the measurements to ascertain penetration (measured in inches), bullet expansion, and retained bullet weight. Finally, the volume of tissue displaced (wound size) by the passage of the bullet was computed in cubic inches and recorded.
The Results
Although penetration and wound size govern handgun wounding effectiveness, penetration is the more critical element. Therefore, a minimum standard of 12" of penetration in the gelatin was established. The following penetration results indicate the number and percentage of rounds in each caliber that met or exceeded the 12" minimum:
10mm - 39 shots out of 40 (97.5%) .45 - 37 shots out of 40 (92.5%) 9mm - 27 shots out of 40 (67.5%)
As a point of reference, the standard issue .38 Special, 158 grain lead hollowpoint round was fired through the battery of tests. Although the .38 was not a "test" round, and therefore not fired under the same strict test controls, the penetration performance was similar to that of the 9mm, producing acceptable penetration 67.5% of the time.
It should be noted that no maximum penetration standard was established. This reflects the judgment that underpenetration of a handgun bullet presents a far greater risk to the law enforcement officer than overpenetration does to an innocent bystander. Considering that approximately 80% of the rounds fired by law enforcement officers engaged in violent encounters do not strike the intended targets, it was deemed somewhat unrealistic to attach too much significance to the potential risks of overpenetration on the part of those that do. Nevertheless, in assessing the potential volume of wounds created by the test bullets, greater attention was given to the potential tissue displaced up to a depth of 18". For practical purposes, penetration beyond that range would most likely carry the bullet outside the body.
Averaging the volumetric results over all eight test events, the 10mm and .45 displaced similar volumes of tissue within the desirable penetration range of 18"-4.11 and 4.22 cubic inches respectively-©well beyond that displaced by the 9mm and .38-ªwhich respectively measured 2.82 and 2.16 cubic inches.
As an additional consideration, the 10mm was by far the most accurate round tested, consistently providing one hole 10©shot groups at 25 yards of less than an inch (0.77" average) with both handloaded and factory ammunition built to FBI specifications. By contrast, the 9mm averaged 2.3" and the .45 averaged 2".
CONCLUSION
The conclusion was obvious. The best performing round within the parameters of the FBI's test protocol was the 10mm. Accordingly, the Director of the FBI approved the recommendation that the new 10mm cartridge be adopted as the standard caliber for a new FBI pistol, and that the new pistol be procured in sufficient quantities to replace existing revolvers.
The tests that led to this decision by the FBI are available, on request, to interested law enforcement agencies. Moreover, ammunition testing will continue, and extend to other calibers and bullets available for law enforcement use. As additional test results are compiled, quarterly updates will be automatically mailed to recipients of the original test report. Requests for the test report entitled "Ammunition Test Results" should be mailed to :
Firearms Training Unit
FBI Academy
Quantico, VA 22135
FBI Bullet Performance Criteria
1. PENETRATION
a. Minimum Acceptable-12
b. Maximum Desirable-18
2. SIZE OF THE WOUND (Volume)
a. Frontal Area of Bullet
b. Depth of Penetration
FBI Standardized Ammunition Tests
Test 1 - Bare Gelatin @ 10 feet
Test 2 - Heavy Clothing @ 10 feet
Test 3 - 20 gauge Steel @ 10 feet
Test 4 - Wallboard @ 10 feet
Test 5 - Plywood @ 10 feet
Test 6 - Auto Windshield Glass @ 10 feet
Test 7 - Light Clothing @ 20 yards
Test 8 - Auto Glass @ 20 yards
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
--------------------------------------------------------------------------------
THE FBI'S 10MM PISTOL
By JOHN C. HALL
Special Agent/Unit Chief
Firearms Training Unit
FBI Academy
Quantico, VA
For several decades, FBI Agents carried the .38 caliber revolver as a standard firearm. Now, after extensive testing and evaluation, the FBI is converting to a new semiautomatic pistol. The new pistol, built to FBI specifications and chambered for a new cartridge; the 10mm, will be issued to all FBI Agents to replace existing revolvers. This article describes the process that led to this decision.
BACKGROUND
The authority for FBI Agents to carry firearms was first granted in 1934. Although pistols were sometimes issued or permitted on a limited basis, the revolver predominated as the FBI sidearm. The first significant shift occurred in 1981, when Special Weapons and Tactics (SWAT) teams were equipped with large capacity 9mm pistols. Since then, 9mm pistols have also become the issue weapons for the FBI's Hostage Rescue Team (HRT) and special surveillance teams.
For the general Agent population, however, revolvers remained the issue weapon, though the increasing use of pistols reflected a growing recognition that the modern pistol provides certain advantages over the revolver. Primarily, pistols are generally more compact and portable and provide a larger ammunition capacity. They are also quicker and easier to reload. Moreover, experience has shown that pistols are generally easier to shoot quickly and accurately due to the self©cocking operation of the slide following each shot and the more efficient transmission of recoil. What is most important, however, is that pistols have proven to be durable and reliable.
Undoubtedly, interest in pistols intensified when innovative designs of the weapon began to appear on the market during the early 1980s. Whereas the basic revolver design remains much as it was at the turn of the century, the pistol has been virtually refashioned in recent years, providing a wide range of such innovative features as double©stacked large capacity magazines, double©action triggers, ambidextrous controls, multiple safety devices, and endless varieties of shapes and sizes.
Meanwhile, other events entered into the picture. Instances where law enforcement officers were confronting more violent, heavily armed subjects appeared to be on the rise. Theincreasing use of semiautomatic and even fully automatic weapons by certain segments of the criminal element began to raise concerns about the adequacy of law enforcement armament.
SELECTION OF A NEW HANDGUN
In 1987, new impetus was given to the FBI's ongoing evaluation of firearms and ammunition. The Firearms Training Unit, located at the FBI Academy in Quantico, VA, set out to identify the best possible handgun for FBI Agents. Firearms training experts undertook a major testing project to evaluate a variety of 9mm and .45 caliber pistols then on the market. While several of the pistols tested were effective, none possessed all of the features desired in a general issue FBI weapon. The challenge was to dev elop a pistol that met the needs of the FBI. In the meantime, as a response to a growing perception within Agent ranks that a pistol was preferable to the revolver, the Director of the FBI authorized Agents to use personally owned pistols, either 9mm or .45 caliber, as long as the weapons were of approved manufacture and design and the training and qualification standards were met.
A Question of Caliber
The most critical, and controversial, issue relating to the selection of a new FBI handgun was that of caliber. Questions have been raised not only about the adequacy of some weapons but also about the wounding effectiveness of some ammunition. Case accounts of shootings document the fact that subjects receiving fatal, but not incapacitating, wounds have been able to return fire and inflict further damage.
Wound Ballistics
As a means of resolving the problem, the FBI convened a Wound Ballistics Seminar at the FBI Academy in September 1987. The participants included noted individuals from the scientific and medical communities from throughout the Nation who possessed relevant expertise in the field of wound ballistics. One of the primary purposes of the seminar was to identify the performance criteria of a bullet most likely to inflict an incapacitating wound on a human target.
A second purpose of the seminar was to determine, if possible, which of the two calibers, the 9mm or the .45, was likely to be most effective in accomplishing that goal. And, although the seminar was unsuccessful in conclusively resolving the caliber question, it did identify the desirable performance criteria of an effective bullet.
Incapacitation, in the law enforcement context, may be simply described as bringing about the immediate cessation of hostile or threatening activities. Incapacitation may result from psychological or physiological factors. Psychologically, some individuals are predisposed to fall down at the sound of gunfire, while others may continue to fight even though they are seriously-©even fatally-©wounded. Because a particular person's psychological response to a gunshot wound cannot be predicted, ammunition performance must be viewed from the perspective of physiological incapacitation.
The seminar participants unanimously concluded that physiological incapacitation can be accomplished in one of two ways©©damage to the central nervous system (the brain or upper spinal column) or significant loss of blood. Because the placement of a shot in the relatively small, highly mobile target area of the brain cannot be counted upon in an armed confrontation, a bullet must therefore be capable of penetrating the body sufficiently to pass through major arteries and blood- bearing organs to ensure timely physiological incapacitation. Without adequate penetration, physiological incapacitation cannot be attained. Given adequate penetration, the only reliable way to increase the effectiveness of the wound is to increase its size, thus increasing the amount of tissue damage and the rate of hemorrhage. Thus, the FBI's test program was designed to evaluate bullet penetration and wound size.
Ammunition Test Design
With the performance criteria acquired from the Wound Ballistics Seminar, the next step was to design and construct a series of ammunition tests to measure the performance of different rounds against those standards. For that purpose, the Firearms Training Unit established a working group which included personnel from the Special Operations and Research Unit, the Hostage Rescue Team, and the Institutional Research and Development Unit.
The tests were designed to simulate factors realistically. Therefore, if the effects of bullets upon human tissue were to be realistically measured, a substance that would duplicate human tissue was needed. Based upon the research of Dr. Martin Fackler, Director of the Army's Wound Ballistics Laboratory, at the Letterman Institute in San Francisco, 10% ballistic gelatin was selected to simulate soft human muscle tissue. Eight separate penetration tests were conducted by firing bullets into this substanc e.
Also, since experience demonstrated that bare tissue is seldom visible on a target in a violent confrontation, seven of the eight tests included covering the gelatin with typical clothing material (cotton T©shirt material, flannel shirt material, 10 oz. down in a nylon carrier, and denim). To assure validity and standardization, clothing manufacturers were consulted to determine the average thread count in typical underclothing, shirts, and jackets.
Other factors were then considered. Because FBI Agents frequently confront subjects in vehicles, behind doors or walls, and at various distances, clothed gelatin was placed behind windshield glass, car door metal, plaster board and plywood. Again, manufacturers in the construction and automobile industries were consulted to assure that the materials used replicated substances that bullets would have to pass through in real©life situations. While most of the test shots were fired from a distance of 10 feet, some of the tests were conducted at 20 yards to assess the effects of distance and velocity loss on penetration potent ial.
Five shots were fired in each of the 8 penetration tests, providing a total of 40 shots for each caliber or bullet type tested.
The Competing Calibers
Once the tests were designed, a decision had to be made regarding the calibers to be tested. In pistol cartridges, the two most obvious contenders were the 9mm and .45. The 9mm round tested was the 147 grain subsonic hollow point round produced by Winchester; the .45 round selected for the test was the Remington 185 grain hollow point. The selection of these particular cartridges for testing was based, in large part, on the consensus of the Wound Ballistic Workshop participants that these bullets should p rovide superior penetration over other hollow point bullets in their respective calibers.
In the meantime, a separate research and development project had been undertaken with the 10mm cartridge to assess its application to law enforcement work. Although the 10mm (.40 caliber) is a relatively new cartridge, with few weapons presently chambered for it, its unique position halfway in size between the 9mm (.35 caliber) and the .45 appeared to offer the possibility of a third viable law enforcement pistol cartridge. In addition, unlike its other competitors, the potential of the new cartridge was virtually untapped.
Samples of commercially available 10mm ammunition were acquired and preliminarily evaluated as to suitability for law enforcement use. The high chamber pressures generated by the commercial loadings, with the resultant heavy recoil and muzzle blast, tended to offset the otherwise excellent performance of the round. Therefore, the FBI Firearms Training Unit decided to create a new loading for the 10mm, one with velocities comparable to those of the competing 9mm and .45 cartridges. A 180 grain hollow poi nt bullet was acquired and handloaded to a velocity of 950 feet per second. This loading not only matched the velocities of the other two cartridges, but it also dramatically reduced recoil and muzzle blast.
In the absence of factory ammunition built to the desired specifications, the 10mm rounds initially subjected to the test protocol were those handloaded by the Firearms Training Unit staff. Subsequently, factory©loaded 10mm ammunition was acquired and built to the desired specifications, which actually met or surpassed the performance of the handloaded test ammunition.
The Test Procedures
Because the objective was to test ammunition and not weapons, the initial tests were conducted with industry standard test barrels. These barrels are built to standards established by the Sporting Arms and Ammunition Manufacturing Institute (SAAMI) and are tailored to optimize the ballistic efficiency of each caliber. Test barrel length is determined by the internal ballistics of the caliber. Consequently, the barrel lengths vary with each caliber. For example, the optimal test barrel for the 9mm is 4" i n length, while those of the 10mm and .45 are 6".
The immediate concern was the possibility that the longer test barrels for the 10mm and .45 would provide an advantage by increasing their velocities. In reality, it was discovered that increased velocity actually diminishes the penetration performance of hollow point bullets in gelatin by increasing the rate and degree of expansion. It was noted, for example, that both the 10mm and .45 achieved lower velocities, but greater penetration, when fired from shorter pistol barrels than when fired from the long er test barrels with somewhat higher velocities. Thus, the longer test barrels used with the 10mm and .45 worked as a handicap for those two calibers by lessening the degree of penetration. That handicap would have been eliminated by using test barrels of equal lengths, and the disparity between the penetration performance of the 9mm and the two other calibers would have been even greater than that actually attained. Since the longer test barrels were not giving any advantage to the 10mm and the .45 calib er (quite the contrary), the tests were continued with existing equipment.
After initial tests to measure velocity and accuracy, 40 rounds of each caliber were fired by FBI firearms personnel to measure penetration and wound volume. Following each shot, red dye was injected into the wound channel created by the passage of the bullet into the gelatin, and a photograph was taken. Then a separate team from the Institutional Research and Development Unit conducted the measurements to ascertain penetration (measured in inches), bullet expansion, and retained bullet weight. Finally, the volume of tissue displaced (wound size) by the passage of the bullet was computed in cubic inches and recorded.
The Results
Although penetration and wound size govern handgun wounding effectiveness, penetration is the more critical element. Therefore, a minimum standard of 12" of penetration in the gelatin was established. The following penetration results indicate the number and percentage of rounds in each caliber that met or exceeded the 12" minimum:
10mm - 39 shots out of 40 (97.5%) .45 - 37 shots out of 40 (92.5%) 9mm - 27 shots out of 40 (67.5%)
As a point of reference, the standard issue .38 Special, 158 grain lead hollowpoint round was fired through the battery of tests. Although the .38 was not a "test" round, and therefore not fired under the same strict test controls, the penetration performance was similar to that of the 9mm, producing acceptable penetration 67.5% of the time.
It should be noted that no maximum penetration standard was established. This reflects the judgment that underpenetration of a handgun bullet presents a far greater risk to the law enforcement officer than overpenetration does to an innocent bystander. Considering that approximately 80% of the rounds fired by law enforcement officers engaged in violent encounters do not strike the intended targets, it was deemed somewhat unrealistic to attach too much significance to the potential risks of overpenetration on the part of those that do. Nevertheless, in assessing the potential volume of wounds created by the test bullets, greater attention was given to the potential tissue displaced up to a depth of 18". For practical purposes, penetration beyond that range would most likely carry the bullet outside the body.
Averaging the volumetric results over all eight test events, the 10mm and .45 displaced similar volumes of tissue within the desirable penetration range of 18"-4.11 and 4.22 cubic inches respectively-©well beyond that displaced by the 9mm and .38-ªwhich respectively measured 2.82 and 2.16 cubic inches.
As an additional consideration, the 10mm was by far the most accurate round tested, consistently providing one hole 10©shot groups at 25 yards of less than an inch (0.77" average) with both handloaded and factory ammunition built to FBI specifications. By contrast, the 9mm averaged 2.3" and the .45 averaged 2".
CONCLUSION
The conclusion was obvious. The best performing round within the parameters of the FBI's test protocol was the 10mm. Accordingly, the Director of the FBI approved the recommendation that the new 10mm cartridge be adopted as the standard caliber for a new FBI pistol, and that the new pistol be procured in sufficient quantities to replace existing revolvers.
The tests that led to this decision by the FBI are available, on request, to interested law enforcement agencies. Moreover, ammunition testing will continue, and extend to other calibers and bullets available for law enforcement use. As additional test results are compiled, quarterly updates will be automatically mailed to recipients of the original test report. Requests for the test report entitled "Ammunition Test Results" should be mailed to :
Firearms Training Unit
FBI Academy
Quantico, VA 22135
FBI Bullet Performance Criteria
1. PENETRATION
a. Minimum Acceptable-12
b. Maximum Desirable-18
2. SIZE OF THE WOUND (Volume)
a. Frontal Area of Bullet
b. Depth of Penetration
FBI Standardized Ammunition Tests
Test 1 - Bare Gelatin @ 10 feet
Test 2 - Heavy Clothing @ 10 feet
Test 3 - 20 gauge Steel @ 10 feet
Test 4 - Wallboard @ 10 feet
Test 5 - Plywood @ 10 feet
Test 6 - Auto Windshield Glass @ 10 feet
Test 7 - Light Clothing @ 20 yards
Test 8 - Auto Glass @ 20 yards
The Ten Essentials
The Ten Essentials
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NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
--------------------------------------------------------------------------------
The Ten Essentials
By Scott Stoddard
"DON'T leave home without it." But what good will a green plastic credit card do you 20 miles from the nearest paved road? What do you really need when out away from civilization?
Experienced outdoor enthusiasts know what items are most important to bring - even for short walks or hikes out of base camp. The "10 Essentials" are items that cannot be improvised from materials lying on the forest floor. To be found without these few items, even only a few miles from camp or cabin, can spell disaster.
The standard list of 10 essentials varies slightly depending on which source you go to. The Boy Scouts have their list, the Sierra Club has another, and the Mountaineers in their outdoor bible, Mountaineering: The Freedom of the Hills, have come up with another variation. They all incorporate the same basic items.
The following list is not to be considered cast in concrete - each survivalist should customize his or her own kit for the barest minimum of supplies. Note that the first three items are for finding your way, the second three are for your protection, and the last four are for emergencies.
1. A MAP of the area you will be hiking, canoeing, or camping should be detailed enough so that you can find man-made items like trails, unimproved roads, power lines, etc., and natural features such as rivers, streams, hills and other terrain landmarks that will guide you. A U.S Geological Survey Topographical map has all of these features and more. For an index to topo maps in your home state contact: U.S. Geological Survey, Map Distribution Section, Federal Center, Box 25286, Denver, CO 80225; (303) 236-7477. A 365 page book titled, The Map Catalog, (Every kind of map and chart on Earth and even some above it), is available from: High Country Enterprise, P.O. Box 746, Saguache, CO 81149; (719) 655-2432.
2. A map without a COMPASS is almost useless unless you possess a sixth sense in direction finding. I prefer the liquid filled "Silva" or "Suunto" compasses. These have straight edges that are useful in plotting bearings. Military lensatic compasses are more bulky and don't have a clear base making map reading through the compass impossible. With both map and compass you should be able to "orient" the map by lining up magnetic north on the compass with the magnetic north arrow printed on the map. Once you do this, you'll be able to identify terrain features and plot your course.
3. Be sure that the FLASHLIGHT you bring doesn't have a switch that is easily turned on and off. You may find that it has been accidentally on all day, and when you need it the batteries will be already worn out. In that case don't put the batteries inside the unit until you are required to use it. Even if you have the most advanced, water proof machined aluminum light source, bring a spare bulb and spare alkaline batteries just in case. A Mini- Mag Lite will fit in the smallest of 10 essential kits but may not be adequate for all-night travel. Headlamps are useful for cave exploring and when the hands are otherwise occupied.
4. On one trip to the top of an 11,000 foot peak I forgot my SUNGLASSES and I nearly went snowblind. After tiring of looking through my balled-up fists I finally had to cut slits in some cardboard and jury-rig some Eskimo sunglasses. Sunglasses are available today that stop 99 percent of ultraviolet light. Polycarbonate lenses with "wraparound" designs provide more protection against wind and side glare. Glacier glasses are recommended for snowy conditions. They usually have polarized lenses and leather side shields to block out the side glare. Buy some retaining straps when you purchase your sunglasses. Croakies or Chums cost less than $5 and will prevent damage or loss of your expensive eye wear. Add some sunscreen to your kit for total solar protection.
5. EXTRA FOOD and WATER. This category puzzles me a bit. Does it mean that I should have two water bottles filled with water and two bags of trail mix? The amount of water you bring should be determined by the length of the trip and the temperature and physical demand put on your body. Water should be used as needed and not rationed out,(i.e.,a few ounces now and no more for another hour). If your body needs water, it needs it now not three hours from now! Water purification tablets might help you use other water sources. As far as food, some hikers throw cans of sardines or tuna fish into their packs knowing that they wouldn't eat it unless there was an emergency. Normal trail foods (dried fruits, nuts, and granola) should be eaten at regular intervals to resupply the body with energy. Pemmican is one of the most concentrated high energy foods you can carry. See the Oct. 1991 ASG issue on page 57 for directions on its preparation.
6. Once again, the EXTRA CLOTHING you bring is determined by the time of the year and the weather. A breezy summer hike may require only a poncho for rain protection and a light nylon wind jammer for possible cold. A day snow hike gets more complicated. An extra jacket or sweater may do, but if you will be in extreme mountain conditions, a bivouac sack, insulation pad, and a winter sleeping bag may be the only thing that will save you should the weather go bad. In normal conditions you should at least throw a metalized space blanket into your kit. This with a poncho can be used to rig up an improvised lean-to shelter. Tape the space blanket to the poncho for support, tie the poncho to trees to form a lean-to and then build a fire in front. The space blanket will reflect the heat of the fire back on to you.
7. Expensive WATERPROOFED MATCHES have always seemed a little too gimmicky for my taste. Strike anywhere wood matches are a lot cheaper and can be stored in a waterproof container such as an empty plastic 35mm film can. If they're too long, just clip off the ends to the right length. A more convenient item for starting fires can be found at your local liquor or convenience store. Throw-away plastic cigarette lighters work well and some have adjustable flames in case you need "blow torch" action. Other fire sparkers such as the flint/magnesium bars on key chains are good back-ups should you lose your matches or lighter.
8. FIRESTARTERS. In this category you can include a regular paraffin candle (store inside a plastic bag so it doesn't melt in your pack), commercial firestarter tablets, Sterno, or my favorite - Hexamine tablets that are available at most Army/Navy surplus stores. Hexamine tablets won't evaporate like Trioxane Fuel Bars do when the wrapper is ripped, and come six tablets to a small cardboard tube.
A firestarter is used only when conditions make it difficult to start a fire. Preparation is the key to fire building. You need plenty of kindling sticks or pieces of wood split thin with your knife to make the larger diameter branches catch. Most people begin their fires with inadequate supplies of tinder and kindling and are frustrated when they can't get a three inch thick log to catch fire.
9. A POCKET KNIFE is your most important 10 essentials item. Among other things it helps in first aid, food preparation, and fire building. As long as you have a knife you can make fire. Striking steel on any flint-like rock will produce sparks that can catch fire in carefully prepared tinder and kindling - materials you have gathered and prepared using the knife. More elaborate versions of pocket knives contain a treasure chest of useful tools: saws, tweezers, scissors, screwdrivers, awls, toothpicks, can openers, etc A good Swiss Army knife will bring out the MacGyver in all of us. Don't forget this item!
10. A FIRST AID KIT really isn't one item but a collection of items that can contain the bare minimum of bandaids, aspirin, and iodine or on the other extreme contain suture kits, chemically activated cold packs and prescription drugs. This is where you will have to really do some customizing and personalizing. I store my first aid items in a plastic Zip Loc bag so that I can see everything inside and protect them from the weather. Along with an assortment of bandaids, gauze pads, and Steri-Strips, are the following: insect repellent, sunscreen, lip balm with SPF 21, triple antibiotic ointment, small bottle of Hibiclens Surgical Scrub, Aspirin, Diasorb tablets for diarrhea, Actifed (decongestant), Bonine (motion sickness), and Benadryl (antihistamine). Other items that are helpful are: a needle for splinter extraction, moleskin or Spenco Second Skin for blisters, Ace bandage, small needle-nose pliers, single-edge razor blades, and Calamine cream for insect bites.
The "11th" item of the 10 essentials most people carry is toilet paper. Other "essentials" I bring include: an Air Force type signal mirror, 50 feet of parachute cord, mini-Leatherman tool, and plastic fluorescent marking tape for trail marking. You might want to add a pocket signal flare and other items such as a smoke generator for signaling.
Your 10 essentials kit can be packaged in a number of ways. The most convenient is a small day pack. Day packs will hold your water bottle, extra clothing and food for most daytime trips. Get one made out of Cordura nylon with padded straps.
For extensive mountain bike rides many cyclists like to use waist packs or fanny packs to store their emergency gear and a banana or two. A waist pack is generally cooler to wear and provides for a lower center of gravity. Water is normally carried on the frame of the bicycle, so the packs can be smaller and lighter.
The last essential that needs to be taken on all your trips into the wilderness won't fit in a survival kit. It's called common sense and is a prime commodity in both the city and in the outdoors. If it looks like rain - don't go. If it looks too high - stay back. If it's getting dark - get back to your base. By avoiding unnecessary problems and dangers you will save on your own personal wear and tear, and probably get back home in one piece. However, if something does come up, at least you know you've got those 10 important items stowed away in your rucksack.
--------------------------------------------------------------------------------
NOTICE: TO ALL CONCERNED Certain text files and messages contained on this site deal with activities and devices which would be in violation of various Federal, State, and local laws if actually carried out or constructed. The webmasters of this site do not advocate the breaking of any law. Our text files and message bases are for informational purposes only. We recommend that you contact your local law enforcement officials before undertaking any project based upon any information obtained from this or any other web site. We do not guarantee that any of the information contained on this system is correct, workable, or factual. We are not responsible for, nor do we assume any liability for, damages resulting from the use of any information on this site.
--------------------------------------------------------------------------------
The Ten Essentials
By Scott Stoddard
"DON'T leave home without it." But what good will a green plastic credit card do you 20 miles from the nearest paved road? What do you really need when out away from civilization?
Experienced outdoor enthusiasts know what items are most important to bring - even for short walks or hikes out of base camp. The "10 Essentials" are items that cannot be improvised from materials lying on the forest floor. To be found without these few items, even only a few miles from camp or cabin, can spell disaster.
The standard list of 10 essentials varies slightly depending on which source you go to. The Boy Scouts have their list, the Sierra Club has another, and the Mountaineers in their outdoor bible, Mountaineering: The Freedom of the Hills, have come up with another variation. They all incorporate the same basic items.
The following list is not to be considered cast in concrete - each survivalist should customize his or her own kit for the barest minimum of supplies. Note that the first three items are for finding your way, the second three are for your protection, and the last four are for emergencies.
1. A MAP of the area you will be hiking, canoeing, or camping should be detailed enough so that you can find man-made items like trails, unimproved roads, power lines, etc., and natural features such as rivers, streams, hills and other terrain landmarks that will guide you. A U.S Geological Survey Topographical map has all of these features and more. For an index to topo maps in your home state contact: U.S. Geological Survey, Map Distribution Section, Federal Center, Box 25286, Denver, CO 80225; (303) 236-7477. A 365 page book titled, The Map Catalog, (Every kind of map and chart on Earth and even some above it), is available from: High Country Enterprise, P.O. Box 746, Saguache, CO 81149; (719) 655-2432.
2. A map without a COMPASS is almost useless unless you possess a sixth sense in direction finding. I prefer the liquid filled "Silva" or "Suunto" compasses. These have straight edges that are useful in plotting bearings. Military lensatic compasses are more bulky and don't have a clear base making map reading through the compass impossible. With both map and compass you should be able to "orient" the map by lining up magnetic north on the compass with the magnetic north arrow printed on the map. Once you do this, you'll be able to identify terrain features and plot your course.
3. Be sure that the FLASHLIGHT you bring doesn't have a switch that is easily turned on and off. You may find that it has been accidentally on all day, and when you need it the batteries will be already worn out. In that case don't put the batteries inside the unit until you are required to use it. Even if you have the most advanced, water proof machined aluminum light source, bring a spare bulb and spare alkaline batteries just in case. A Mini- Mag Lite will fit in the smallest of 10 essential kits but may not be adequate for all-night travel. Headlamps are useful for cave exploring and when the hands are otherwise occupied.
4. On one trip to the top of an 11,000 foot peak I forgot my SUNGLASSES and I nearly went snowblind. After tiring of looking through my balled-up fists I finally had to cut slits in some cardboard and jury-rig some Eskimo sunglasses. Sunglasses are available today that stop 99 percent of ultraviolet light. Polycarbonate lenses with "wraparound" designs provide more protection against wind and side glare. Glacier glasses are recommended for snowy conditions. They usually have polarized lenses and leather side shields to block out the side glare. Buy some retaining straps when you purchase your sunglasses. Croakies or Chums cost less than $5 and will prevent damage or loss of your expensive eye wear. Add some sunscreen to your kit for total solar protection.
5. EXTRA FOOD and WATER. This category puzzles me a bit. Does it mean that I should have two water bottles filled with water and two bags of trail mix? The amount of water you bring should be determined by the length of the trip and the temperature and physical demand put on your body. Water should be used as needed and not rationed out,(i.e.,a few ounces now and no more for another hour). If your body needs water, it needs it now not three hours from now! Water purification tablets might help you use other water sources. As far as food, some hikers throw cans of sardines or tuna fish into their packs knowing that they wouldn't eat it unless there was an emergency. Normal trail foods (dried fruits, nuts, and granola) should be eaten at regular intervals to resupply the body with energy. Pemmican is one of the most concentrated high energy foods you can carry. See the Oct. 1991 ASG issue on page 57 for directions on its preparation.
6. Once again, the EXTRA CLOTHING you bring is determined by the time of the year and the weather. A breezy summer hike may require only a poncho for rain protection and a light nylon wind jammer for possible cold. A day snow hike gets more complicated. An extra jacket or sweater may do, but if you will be in extreme mountain conditions, a bivouac sack, insulation pad, and a winter sleeping bag may be the only thing that will save you should the weather go bad. In normal conditions you should at least throw a metalized space blanket into your kit. This with a poncho can be used to rig up an improvised lean-to shelter. Tape the space blanket to the poncho for support, tie the poncho to trees to form a lean-to and then build a fire in front. The space blanket will reflect the heat of the fire back on to you.
7. Expensive WATERPROOFED MATCHES have always seemed a little too gimmicky for my taste. Strike anywhere wood matches are a lot cheaper and can be stored in a waterproof container such as an empty plastic 35mm film can. If they're too long, just clip off the ends to the right length. A more convenient item for starting fires can be found at your local liquor or convenience store. Throw-away plastic cigarette lighters work well and some have adjustable flames in case you need "blow torch" action. Other fire sparkers such as the flint/magnesium bars on key chains are good back-ups should you lose your matches or lighter.
8. FIRESTARTERS. In this category you can include a regular paraffin candle (store inside a plastic bag so it doesn't melt in your pack), commercial firestarter tablets, Sterno, or my favorite - Hexamine tablets that are available at most Army/Navy surplus stores. Hexamine tablets won't evaporate like Trioxane Fuel Bars do when the wrapper is ripped, and come six tablets to a small cardboard tube.
A firestarter is used only when conditions make it difficult to start a fire. Preparation is the key to fire building. You need plenty of kindling sticks or pieces of wood split thin with your knife to make the larger diameter branches catch. Most people begin their fires with inadequate supplies of tinder and kindling and are frustrated when they can't get a three inch thick log to catch fire.
9. A POCKET KNIFE is your most important 10 essentials item. Among other things it helps in first aid, food preparation, and fire building. As long as you have a knife you can make fire. Striking steel on any flint-like rock will produce sparks that can catch fire in carefully prepared tinder and kindling - materials you have gathered and prepared using the knife. More elaborate versions of pocket knives contain a treasure chest of useful tools: saws, tweezers, scissors, screwdrivers, awls, toothpicks, can openers, etc A good Swiss Army knife will bring out the MacGyver in all of us. Don't forget this item!
10. A FIRST AID KIT really isn't one item but a collection of items that can contain the bare minimum of bandaids, aspirin, and iodine or on the other extreme contain suture kits, chemically activated cold packs and prescription drugs. This is where you will have to really do some customizing and personalizing. I store my first aid items in a plastic Zip Loc bag so that I can see everything inside and protect them from the weather. Along with an assortment of bandaids, gauze pads, and Steri-Strips, are the following: insect repellent, sunscreen, lip balm with SPF 21, triple antibiotic ointment, small bottle of Hibiclens Surgical Scrub, Aspirin, Diasorb tablets for diarrhea, Actifed (decongestant), Bonine (motion sickness), and Benadryl (antihistamine). Other items that are helpful are: a needle for splinter extraction, moleskin or Spenco Second Skin for blisters, Ace bandage, small needle-nose pliers, single-edge razor blades, and Calamine cream for insect bites.
The "11th" item of the 10 essentials most people carry is toilet paper. Other "essentials" I bring include: an Air Force type signal mirror, 50 feet of parachute cord, mini-Leatherman tool, and plastic fluorescent marking tape for trail marking. You might want to add a pocket signal flare and other items such as a smoke generator for signaling.
Your 10 essentials kit can be packaged in a number of ways. The most convenient is a small day pack. Day packs will hold your water bottle, extra clothing and food for most daytime trips. Get one made out of Cordura nylon with padded straps.
For extensive mountain bike rides many cyclists like to use waist packs or fanny packs to store their emergency gear and a banana or two. A waist pack is generally cooler to wear and provides for a lower center of gravity. Water is normally carried on the frame of the bicycle, so the packs can be smaller and lighter.
The last essential that needs to be taken on all your trips into the wilderness won't fit in a survival kit. It's called common sense and is a prime commodity in both the city and in the outdoors. If it looks like rain - don't go. If it looks too high - stay back. If it's getting dark - get back to your base. By avoiding unnecessary problems and dangers you will save on your own personal wear and tear, and probably get back home in one piece. However, if something does come up, at least you know you've got those 10 important items stowed away in your rucksack.
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