Ballistics

Ballistics From Wikipedia, the free encyclopedia

Jump to: navigation, search For other uses, see Ballistics (disambiguation). Ballistics (gr. βάλλειν ('ba'llein'), "throw") is the science of mechanics that deals with the flight, behavior, and effects of projectiles, especially bullets, gravity bombs, rockets, or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance. A ballistic body is a body which is free to move, behave, and be modified in appearance, contour, or texture by ambient conditions, substances, or forces, as by the pressure of gases in a gun, by rifling in a barrel, by gravity, by temperature, or by air particles. A ballistic missile is a missile only guided during the relatively brief initial powered phase of flight and its course is subsequently governed by the laws of classical mechanics. In the field of forensic science, forensic ballistics is the science of analyzing firearm usage in crimes.

[edit] Gun ballistics Gun ballistics is the study of projectiles from the time of shooting to the time of impact with the target. Gun ballistics is often broken down into the following four categories, which contain detailed information on each category:[1] • •

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Internal ballistics, the study of the processes originally accelerating the projectile, for example the passage of a bullet through the barrel of a rifle; Transition ballistics, (sometimes called intermediate ballistics) the study of the projectile's behavior when it leaves the barrel and the pressure behind the projectile is equalized. External ballistics, the study of the passage of the projectile through space or the air; and Terminal ballistics, the study of the interaction of a projectile with its target, whether that be flesh (for a hunting bullet), steel (for an anti-tank round), or even furnace slag (for an industrial slag disruptor).

[edit] Forensic ballistics A forensic ballistics experiment Forensic ballistics involves analysis of bullets and bullet impacts to determine the type. Separately from ballistics information, firearm and tool mark examinations involve

analysing firearm, ammunition, and tool mark evidence in order to establish whether a certain firearm or tool was used in the commission of a crime. Rifling, which first made an appearance in the 15th century, is the process of making grooves in gun barrels that imparts a spin to the projectile for increased accuracy and range. Bullets fired from rifled weapons acquire a distinct signature of grooves, scratches, and indentations which are of value for matching a fired projectile to a firearm. The first firearms evidence identification can be traced back to England in 1835 when the unique markings on a bullet taken from a victim were matched with a bullet mold belonging to the suspect. When confronted with the damning evidence, the suspect confessed to the crime. The first court case involving firearms evidence took place in 1902 when a specific gun was proven to be the murder weapon. The expert in the case, Oliver Wendell Holmes, had read about firearm identification, and had a gunsmith test-fire the alleged murder weapon into a wad of cotton wool. A magnifying glass was used to match the bullet from the victim with the test bullet. Calvin Goddard, physician and ex-army officer, acquired data from all known gun manufacturers in order to develop a comprehensive database. With his partner, Charles Waite, he catalogued the results of test-firings from every type of handgun made by 12 manufacturers. Waite also invented the comparison microscope. With this instrument, two bullets could be laid adjacent to one another for comparative examination. In 1925 Goddard wrote an article for the Army Ordnance titled "Forensic Ballistics" in which he described the use of the comparison microscope regarding firearms investigations. He is generally credited with the conception of the term "forensic ballistics," though he later admitted it to be an inadequate name for the science. In 1929 the St. Valentine's Day Massacre led to the opening of the first independent scientific crime Ballistic conduction is the unimpeded flow of charge or energy carrying particles over relatively high distances in a material. Normally, transport of electrons (or holes) is dominated by scattering events, which relax the carrier momentum in an effort to bring the conducting material to equilibrium. Thus, ballistic transport in a material is determined by how ballistically conductive that material is. Ballistic conduction differs from superconductivity due to the absence of the Meissner effect in the material. A ballistic conductor would stop conducting if the driving force is turned off, whereas in a superconductor current would continue to flow after the driving supply is disconnected. Ballistic conduction is typically observed in quasi-1D structures, such as carbon nanotubes or silicon nanowires, because of extreme size quantization effects in these materials. Ballistic conduction is not limited to electrons (or holes) but can also apply to

phonons. It is theoretically possible for ballistic conduction to be extended to other quasiparticles, but this has not been experimentally verified.

Bullet From Wikipedia, the free encyclopedia

Jump to: navigation, search This article is about firearms projectiles. For other uses, see Bullet (disambiguation).

Lead soft-point, boat-tailed, copper-jacketed bullets A bullet is a hard projectile propelled by a firearm, sling, or air gun and is normally made from metal. A bullet does not contain explosives, but damages the intended target by tissue or mechanical disruption through impact or penetration. The word "bullet" is sometimes erroneously used to refer to a cartridge, which is the combination of bullet, casing (case or shell), gunpowder and primer. See ammunition. The Oxford English Dictionary definition of a bullet is "a projectile of lead ... for firing from a rifle, revolver etc." [1] However, bullets for air guns are not part of a cartridge

History

Lead sling bullets with a winged thunderbolt engraved on one side and the inscription "take that" on the other side. 4th century BC. From Athens.

Matchlock musket balls, alleged to have been discovered at Naseby battlefield. From the collection of Northampton Museum and Art Gallery. The history of bullets far pre-dates the history of firearms. Originally, bullets were metallic or stone balls used in a sling as a weapon and for hunting. Eventually as firearms were developed these same items were placed in front of an explosive charge of gun powder at the end of a closed tube. As firearms became more technologically advanced, from 1500 to 1800, bullets changed very little. They remained simple round (spherical) lead balls, called rounds, differing only in their diameter The development of the hand culverin and matchlock arquebus brought about the use of cast lead balls as projectiles. "Bullet" is derived from the French word "boulette" which roughly means "little ball". The original musket bullet was a spherical lead ball two sizes smaller than the bore, wrapped in a loosely-fitted paper patch which served to hold the bullet in the barrel firmly upon the powder. (Bullets that were not firmly upon the powder upon firing risked causing the barrel to explode, with the condition known as a "short start".) The loading of muskets was, therefore, easy with the old smooth-bore Brown Bess and similar military muskets. The original muzzle-loading rifle, on the other hand, with a more closely fitting ball to take the rifling grooves, was loaded with difficulty, particularly when the bore of the barrel was dirty from previous firings ("fouled"). For this reason, early rifles were not generally used for military purposes. Early rifle bullets required cloth or leather patches to grip the rifling grooves, and to hold the bullet securely against the powder. The first half of the nineteenth century saw a distinct change in the shape and function of the bullet. In 1826, Delirque, a French infantry officer, invented a breech with abrupt shoulders on which a spherical bullet was rammed down until it caught the rifling grooves. Delirque's method, however, deformed the bullet and was inaccurate.

[edit] Pointed bullets Among the first pointed or "conical" bullets were those designed by Captain John Norton of the British Army in 1823. Norton's bullet had a hollow base which expanded under pressure to engage with a barrel's "rifling" (internal grooves) at the moment of being fired; the British Board of Ordnance rejected it because spherical bullets had been in use for the last 300 years. Renowned English gunsmith William Greener invented the Greener bullet in 1836. It was very similar to Norton's bullet except that the hollow base of the bullet was fitted with a wooden plug which more reliably forced the base of the bullet to expand and catch the rifling. Tests proved that Greener's bullet was extremely effective but it too was rejected for military use because, being two parts, it was judged as being too complicated to produce.

Minié ball ammunition The soft lead bullet that came to be known as the Minié ball, (or minnie ball) was first introduced in 1847 by Claude Étienne Minié (1814? - 1879), a captain in the French Army. It was nearly identical to the Greener bullet. As designed by Minié, the bullet was conical in shape with a hollow cavity in the rear, which was fitted with a little iron cap instead of a wooden plug. When fired, the iron cap would force itself into the hollow cavity at the rear of the bullet, thereby expanding the sides of the bullet to grip and engage the rifling. In 1855, the British adopted the Minié ball for their Enfield rifles. It was in the American Civil War, however, that the Minié ball first saw widespread use. Roughly 90% of the battlefield casualties in this war were caused by Minié balls fired from rifles. Between 1854 and 1857, Sir Joseph Whitworth conducted a long series of rifle experiments, and proved, among other points, the advantages of a smaller bore and, in particular, of an elongated bullet. The Whitworth bullet was made to fit the grooves of the rifle mechanically. The Whitworth rifle was never adopted by the government, although it was used extensively for match purposes and target practice between 1857 and 1866, when it was gradually superseded by Metford's. About 1862 and later, W. E. Metford had carried out an exhaustive series of experiments on bullets and rifling, and had invented the important system of light rifling with increasing spiral, and a hardened bullet. The combined result of the above inventions was that in December 1888 the Lee-Metford small-bore (0.303", 7.70 mm) rifle, Mark I, (photo of cartridge on right) was finally adopted for the British army. The Lee-Metford was the predecessor of the Lee-Enfield.

[edit] The modern bullet

.270 ammunition. Left to Right: 100-grain (6.5 g) - Hollow Point 115-grain (7.5 g) - FMJBT 130-grain (8.4 g) - Soft point, 150-grain (9.7 g) - round nose. .303 inch (7.7 mm) centrefire, FMJ rimmed ammunition The next important change in the history of the rifle bullet occurred in 1883, when Major Rubin, director of the Swiss Laboratory at Thun, invented the copper jacketed bullet; an elongated bullet with a lead core in a copper envelope or jacket. The copper jacketed bullet allows much higher muzzle velocities than lead alone, as copper has a much higher melting point, greater specific heat capacity, and is harder. Lead bullets fired at high velocity may suffer surface melting due to hot gases behind and friction with the bore. European advances in aerodynamics led to the pointed spitzer bullet. By the beginning of the twentieth century, most world armies had begun to transition to spitzer bullets. These bullets flew for greater distances more accurately and carried more energy with them. Spitzer bullets combined with machine guns increased the lethality of the battlefield drastically. The final advancement in bullet shape occurred with the development of the boat tail which is a streamlined base for spitzer bullets. A vacuum is created when air strata moving at high speed passes over the end of a bullet. The streamlined boat tail design aims to eliminate this drag-inducing vacuum by allowing the air to flow alongside the surface of the tapering end, thus eliminating the need for air to turn around the 90-degree angle normally formed by the end of shaped bullets. The resulting aerodynamic advantage is currently seen as the optimum shape for rifle technology. The spitzer boattailed bullet ( Balle "D" ) was first introduced as standard ammunition in a military rifle in 1901, for the French Lebel Mle 1886 service weapon.

[edit] Design

A modern cartridge consists of the following: 1. the bullet itself, which serves as the projectile; 2. the case, which holds all parts together; 3. the propellant, for example gunpowder or cordite; 4. the rim, part of the casing used for loading; 5. the primer, which ignites the propellant. Bullet designs have to solve two primary problems. They must first form a seal with the gun's bore. The worse the seal, the more gas, generated by the rapid combustion of the propellant charge, leaks past the bullet, reducing the efficiency. The bullet must also engage the rifling without damaging the gun's bore. Bullets must have a surface which will form this seal without causing excessive friction. What happens to a bullet inside the bore is termed internal ballistics. A bullet must also be consistent with the next bullet so that shots may be fired precisely. Once it leaves the barrel, it is governed by external ballistics. Here, the bullet's shape is important for aerodynamics, as is the rotation imparted by the rifling. Rotational forces stabilize the bullet gyroscopically as well as aerodynamically. Any asymmetry in the bullet is largely cancelled as it spins. With smooth-bore firearms, a spherical shape was optimum because no matter how it was oriented, it presented a uniform front. These unstable bullets tumbled erratically, but the aerodynamic shape changed little giving moderate accuracy. Generally, bullet shapes are a compromise between aerodynamics, interior ballistics necessities, and terminal ballistics requirements. Another method of stabilization is for the center of mass of the bullet to be as far forward as practical as in the minnie ball or the shuttlecock. This allows the bullet to fly front-forward by means of aerodynamics. See Terminal ballistics and/or Stopping power for an overview of how bullet design affects what happens when a bullet hits something, and how this is affected by its design. What happens to the bullet is dictated as much by what it hits and how it hits, as by the bullet itself (just like how its interaction with air was critical in external ballistics). Bullets are generally designed to penetrate, deform, and/or break apart. For a given material and bullet, which of these happens is determined especially by the strike velocity. Actual bullet shapes are many and varied, and an array of them can be found in any reloading manual that sells bullet moulds. RCBS, one of many makers, offers many different designs, starting with the basic round ball. With a mould, bullets can be made at home for reloading one's own ammunition, where local laws allow. Hand-casting, however, is only time- and cost-effective for solid lead bullets. Cast and jacketed bullets are also commercially available from numerous manufacturers for hand loading and are much more convenient than casting bullets from bulk lead.

[edit] Materials

Bullets for black powder, or muzzle loading firearms, were classically molded from pure lead. This worked well for low speed bullets, fired at velocities of less than 300 m/s (1000 ft/s). For slightly higher speed bullets fired in modern firearms, a harder alloy of lead and tin or typesetter's lead (used to mold Linotype) works very well. For even higher speed bullet use, jacketed coated lead bullets are used. The common element in all of these, lead, is widely used because it is very dense, thereby providing a high amount of mass — and thus, kinetic energy — for a given volume). Lead is also cheap, easy to obtain, easy to work, and melts at a low temperature, making it easy to use in fabricating bullets. •

Lead: Simple cast, extruded, swaged, or otherwise fabricated lead slugs are the simplest form of bullets. At speeds of greater than 300 m/s (1000 ft/s) (common in most handguns), lead is deposited in rifled bores at an ever-increasing rate. Alloying the lead with a small percentage of tin and/or antimony serves to reduce this effect, but grows less effective as velocities are increased. A cup made of harder metal, such as copper, placed at the base of the bullet and called a gas check, is often used to decrease lead deposits by protecting the rear of the bullet against melting when fired at higher pressures, but this too does not solve the problem at higher velocities.

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Jacketed Lead: Bullets intended for even higher-velocity applications generally have a lead core that is jacketed or plated with cupronickel, copper alloys, or steel; a thin layer of harder metal protects the softer lead core when the bullet is passing through the barrel and during flight, which allows delivering the bullet intact to the target. There, the heavy lead core delivers its kinetic energy to the target. Full metal jacket bullets or Ball bullet have the front and sides of the bullet completely encased in the harder metal jacket. Some bullet jackets do not extend to the front of the bullet to aid in expansion and increase lethality. These are called soft points or hollow point bullets. Steel bullets are often plated with copper or other metals for additional corrosion resistance during long periods of storage. Synthetic jacket materials such as nylon and Teflon have been used with limited success.

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Armor Piercing: Jacketed designs where the core material is a very hard, highdensity metal such as tungsten, tungsten carbide, depleted uranium, or steel. A pointed tip is often used, but a flat tip on the penetrator portion is generally more effective.[2]

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Tracer: These have a hollow back, filled with a flare material. Usually this is a mixture of magnesium perchlorate, and strontium salts to yield a bright red color, although other materials providing other colors have also sometimes been used. Tracer material burns out after a certain amount of time. Such ammunition is useful to the shooter as a means of verifying how close the point of aim is to the actual point of impact, and for learning how to point shoot moving targets with rifles. This type of round is also used by all branches of the United States military in combat environments as a signaling device to friendly forces. Normally it is

loaded at a four to one ratio with ball ammunition and is intended to show where you are firing so friendly forces can engage the target as well. The flight characteristics of tracer rounds differ from normal bullets, decreasing in altitude sooner than other bullets, because of increased aerodynamic drag. •

Incendiary: These bullets are made with an explosive or flammable mixture in the tip that is designed to ignite on contact with a target. The intent is to ignite fuel or munitions in the target area, thereby adding to the destructive power of the bullet itself.

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Frangible: Designed to disintegrate into tiny particles upon impact to minimize their penetration for reasons of range safety, to limit environmental impact, or to limit the shoot-through danger behind the intended target. An example is the Glaser Safety Slug.

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Non Toxic: Bismuth, tungsten, steel, and other exotic bullet alloys prevent release of toxic lead into the environment. Regulations in several countries mandate the use of non-toxic projectiles especially when hunting waterfowl. It has been found that birds swallow small lead shot for their gizzards to grind food (as they would swallow pebbles of similar size), and the effects of lead poisoning by constant grinding of lead pellets against food means lead poisoning effects are magnified. Such concerns apply primarily to shotguns, firing pellets (shot) and not bullets, but reduction of hazardous substances (RoHS) legislation has also been applied to bullets on occasion to reduce the impact of lead on the environment at shooting ranges.

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Practice: Made from lightweight materials like rubber, Wax, wood, plastic, or lightweight metal, practice bullets are intended for short-range target work, only. Because of their weight and low velocity, they have limited range.

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Less Lethal, or Less than Lethal: Rubber bullets, plastic bullets, and beanbags are designed to be non-lethal, for example for use in riot control. They are generally low velocity and are fired from shotguns, grenade launchers, paint ball guns, or specially-designed firearms and air gun devices.

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Blanks: Wax, paper, plastic, and other materials are used to simulate live gunfire and are intended only to hold the powder in a blank cartridge and to produce noise. The 'bullet' may be captured in a purpose-designed device or it may be allowed to expend what little energy it has in the air. Some blank cartridges are crimped or closed at the end and do not contain any bullet.

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Blended-Metal: Bullets made using cores made powdered metals other than lead with binder. Sometimes sintered.

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Exploding: Similar to the incendiary bullet, this type of projectile is designed to explode upon hitting a hard surface, preferably the bone of the intended target.Not

to be mistaken for cannon rounds or grenade with fuze devices, these bullets have only a cavity filled with a small amount of low explosive depending on the velocity and deformation upon impact to detonate. Usually produced for hunting airguns with the intent of increasing the bullets effectiveness.

[edit] Treaties The Hague Convention prohibits certain kinds of ammunition for use by uniformed military personnel against the uniformed military personnel of opposing forces. These include projectiles which explode within an individual, poisoned and expanding bullets. Nothing in these treaties prohibits incendiary bullets (tracers) or the use of prohibited bullets on military equipment. These treaties apply even to .22 LR bullets used in pistols, rifles and machine guns. Hence, the High Standard HDM pistol, a .22 LR suppressed pistol, had special bullets developed for it during World War II that were full metal jacketed, in place of the hollowpoint bullets that are more commonly used in .22 LR pistols.

[edit] Bullet abbreviations ACC – Remington Accelerator [3] (see sabot) AP – Armor Piercing (has a steel or other hard metal core) BBWC – Bevel Base Wadcutter BEB – Brass Enclosed Base Blitz – Sierra BlitzKing Bt – Boat-tail BtHP – Boat-tail Hollow Point CB – Cast Bullet CL, C-L – Remington Core-Lokt DEWC – Double Ended Wadcutter EVO, FTX – Hornady LEVERevolution® Flex Tip® eXpanding FMJ – Full Metal Jacket FMC – Full Metal Case FN – Flat Nose FP – Flat Point FST – Winchester Fail

JHC – Jacketed Hollow Cavity JHP – Jacketed Hollow Point JHP/sabot – Jacketed Hollow Point/sabot JSP – Jacketed Soft Point L – Lead L-C – Lead Combat L-T – Lead Target LFN – Long Flat Nose LFP – Lead Flat Point LHP – Lead Hollow Point LRN – Lead Round Nose LSWC – Lead Semiwadcutter LSWC-GC – Lead Semiwadcutter Gas Checked LWC – Lead Wadcutter LTC – Lead Truncated Cone MC – Metal Cased MHP – Match Hollow Point

RNFP – Round Nose Flat Point RNL – Round Nosed Lead SJ – Semi-Jacketed SJHP – Semi-Jacketed Hollow Point SJSP – Semi-Jacketed Soft Point SP – Soft Point SP – Spire Point Sp,SPTZ – Spitzer SpHP – Spitzer Hollow Point SST – Hornady Super Shock Tip SSp – Semi-Spitzer ST – Silver Tip STHP – Silver Tip Hollow Point SWC – Semiwadcutter SX – Super Explosive SXT – Winchester Ranger Supreme Expansion Technology TC – Truncated Cone TMJ – Total Metal Jacket

Safe Talon GC – Gas Check GD – Speer Gold Dot GDHP – Speer Gold Dot Hollow Point GS – Remington Golden Saber HBWC – Hollow Base Wadcutter HC – Hard Cast HP – Hollow Point HPJ – High Performance Jacketed HS – Federal HydraShok HST – Federal Hi-Shok Two J – Jacketed JFP – Jacketed Flat Point

MK – Sierra MatchKing MRWC – Mid-Range Wadcutter NP – Nosler Partition OTM – Open Tip Match OWC – Ogival Wadcutter [4] PB – Lead Bullet PB – Parabellum PL – Remington Power-Lokt PSP – Plated Soft Point PSP, PTDSP – Pointed Soft Point RN – Round Nose

TNT – Speer TNT VMAX – Hornady VMax VLD – Very Low Drag WC – Wadcutter WFN – Wide Flat Nose WFNGC – Wide Flat Nose Gas Check WLN – Wide Long Nose X – Barnes X-Bullet XTP – Hornady Extreme Terminal Performance

Cartridge (firearms) From Wikipedia, the free encyclopedia

(Redirected from Cartridge (weaponry)) Jump to: navigation, search

From left: .50 BMG, .300 Win Mag, .308 Winchester, 7.62x39mm, 5.56x45mm NATO, .22LR. A cartridge, also called a round, packages the bullet, gunpowder and primer into a single metallic case precisely made to fit the firing chamber of a firearm. The primer is a small charge of impact-sensitive chemical that may be located at the center of the case head (centerfire ammunition) or at its rim (rimfire ammunition). Electrically-fired

cartridges have also been made. Caseless ammunition has been made as well. A cartridge without a bullet is called a blank; one that is completely inert is called a dummy

Design

.30-06 Springfield cartridge specifications. This is a rimless cartridge case. Measurements are in inches. The cartridge case seals a firing chamber in all directions except down the bore. A firing pin strikes the primer, igniting it. The spark from the primer ignites the powder. Burning gases from the powder expand the case to seal against the chamber wall. The projectile is then pushed in the direction that releases this pressure, down the barrel. After the projectile leaves the barrel the pressure is released, allowing the cartridge case to be removed from the chamber.

An M4 Carbine, with an ejected case visible in mid-air.

Various cases of assorted common calibers.

Aluminum .44 caliber cases. Automatic and semiautomatic firearms, which extract and eject the case automatically as a part of their operation, sometimes damage the case in the process of ejection. Brass is a commonly used material, as it is resistant to corrosion and ductile enough to be reformed and reloaded several times. However, some low-quality "plinking" ammunition, as well as some military ammunition (mainly from the former Soviet Union and China) is made with steel cases because steel is less expensive than brass. As militaries typically consider small arms cartridge cases to be a disposable, one-time-use affair, the lack of ductility is inconsequential for this application, although the mass of the case affects how much ammunition a soldier can carry. Some ammunition is also made with aluminum cases (see picture). Critical specifications include caliber, bullet weight, expected velocity, maximum pressure, headspace, overall length and primer type. A minor deviation in many of these specifications could result in damage to the firearm, and in extreme cases injury or death of the user. The diameter of a bullet is measured either as a decimal fraction of an inch, or in millimeters. The length of a cartridge case may also be designated in millimeters. Where two numbers are together, the second number can contain a variety of meanings. Frequently the first is the diameter (caliber) of the cartridge, and the second is the length of the cartridge case. For example, the 7.62 x 51 mm uses a bore diameter of 7.62 mm and has an overall case length of 51 mm. In the case of old black powder cartridges, the second number typically refers to the powder charge. For example, the .50-90 Sharps is a .50 caliber bullet (.512) with a nominal charge of 90 grains (5.8 g) of black powder with a case length of 2.50 inches (64 mm). One should be aware that cartridge nomenclature is inconsistent and unhelpful when trying to determine dimensions, tolerances or indeed almost any other characteristic of a given round. The .38 Special actually has a bullet diameter of 0.357 inches (9.1 mm) (jacketed) or 0.358 inches (9.1 mm) (lead) while the case has a diameter of 0.380 inches (9.7 mm). The .357 Magnum is a direct evolution of the .38 special, but differently named, and no reference is made to the longer case. The .30-06 rifle round is a (nominally) 0.3 inches (7.6 mm) caliber round designed in 1906; and the .303 British round may vary wildly in actual dimensions (as do the surviving rifle chambers of its era). Most high-powered guns have relatively small bullets moving at high speeds. This is because while bullet energy increases in direct proportion to bullet weight, it increases in proportion to the square of bullet velocity. Therefore, a bullet going twice as fast has four times the energy (see physics of firearms). Bullet speeds are now limited by starting bore pressures, which in turn are limited by the strength of materials and the weight of gun people are willing to carry. Larger cartridges have more powder, and usually higher velocities.

Of the hundreds of different designs and developments that have occurred, essentially only two basic cartridge designs remain. All current firearms are either rimfire or centerfire. US military small arms suppliers are still trying to perfect electronic firing, which replaces the conventional firing pin and primer with an electrical ignition system wherein an electrical charge ignites the primer.

[edit] Centerfire

Rimmed, centerfire .303 cartridge from WW II. Manufactured by Colonial Ammunition Company, New Zealand. Main article: Centerfire ammunition A centerfire cartridge has a centrally located primer, which in most US made ammunition, and in some (chiefly premium hunting and match ammunition) manufactured in other countries, can be replaced, so that the expensive brass cartridge case can be reused. Such a cartridge is said to be Boxer primed. Most European and Asian military ammunition uses a non-replaceable Berdan primer, which prevents the easy reuse of the case, because the anvil of the primer is an integral part of the case and can be deformed by firing. With care, it can be reloaded. An irregular fighter might more simply reload a Berdan-primed cartridge, since the new "primer" can be as simple as a bit of tin can and a match head, without the multi-stage process required for making a Boxer primer. US military ammunition is Boxer primed.

[edit] Rimfire Main article: Rimfire ammunition Rimfire cartridges, of which only the popular .22 LR remains in common use, were a popular solution before the centerfire design was fully perfected. They can only be used for fairly low powered cartridges, as the case has to be soft enough to be deformed by the firing pin, which detonates the priming compound in the rim. In the past, 9 mm cartridges were available, as well as .177, .25, etc. cartridges. BB and CB caps were common, as well as .22 Short and .22 Long. Today, .22 LR (Long Rifle)accounts for much of rimfire ammunition shot. Recently, a .17 HMR (nominally .172 caliber) rimfire cartridge was released, and has become extremely popular among target shooters as well as small game hunters, due to its high velocity and flat shooting characteristics. .22 LR rounds normally use a soft lead bullet, and can be supersonic or subsonic. They are often copper-washed both for toxicity reasons and to prevent barrel fouling. .22 Magnum cartridges typically contain copper jacketed lead

projectiles. The newer .17 rounds all feature bullets similar in construction to those found in centerfire cartridges, such as copper jacketed lead.

[edit] Semi-automatic vs. Revolver Cartridges Nearly every semi-automatic pistol cartridge is "rimless", or more explicitly has an inset rim that the extractor engages. Revolver cartridges, on the other hand, have a rim at the base of the case which seats into the cylinder block to keep the cartridge from moving too far forward in the cylinder. Certain exceptions apply, namely for .45 caliber rimless cartridges that are held in place at the inset with a half-moon clip, which keeps the otherwise flush bullets held within contact distance of the firing pin. For a visual comparison of similar-sized cartridges with different rims, see .380 ACP (semiautomatic) vs. .38 Special (revolver.)

[edit] Cartridges in use See also table of pistol and rifle cartridges by year There is great variety in the length and diameter of cartridges for the different kinds and calibers of rifles and pistols. The best cartridge for different purposes is subject to much discussion. However, there are standard uses for certain calibers, and these are a reliable guide to recommended uses. It is important to note that equivalent caliber is by no means equivalent power. Generally speaking, "stopping power" is determined by the weight of the bullet, the terminal ballistics of the bullet – does it stay straight and in one piece, tumble, or "mushroom" on impact – and the charge of gunpowder accelerating it. The following list samples only a few very well-known cartridges; for a complete list, see table of pistol and rifle cartridges by year. The list is roughly ordered by cartridge length.

[edit] Jacketing Of Cartridges' Bullets

A cutaway showing a Japanese Navy 7.7 mm rimed rounds as fired by the Type 92 and Type 97 machine guns - copies of Vickers and Lewis designs. The round is effectively interchangeable with .303 British •

RNL - Round Nose Lead - An unjacketed lead bullet. Although largely supplanted by jacketed ammunition, is still common for older revolver cartridges.

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FNL - Flat Nose Lead - Similar to the above, with a flattened nose. Common in Cowboy Action Shooting loads.

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AP - Armor Piercing - A hard bullet made from steel or tungsten alloys in a pointed shape typically covered by a thin layer of lead and/or a copper/brass jacket. The lead and jacket are intended to prevent barrel wear from the hard core materials. For metallic silhouette purposes, AP is slightly worse on unarmored targets than FMJ. This is to indicate the hard AP projectiles' tendency not to deform or reliably tumble/yaw.

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FMJ - Full Metal Jacket - Made with a lead core surrounded by a full covering of brass, copper, or mild steel. These have very little deformation or expansion, but will occasionally yaw/tumble.

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JSP - Jacketed Soft Point - In the late 1800s, the Indian Army arsenal at Dum Dum, near Calcutta, developed a variation of the FMJ design where the jacket did not cover the nose of the bullet. The soft lead nose was found to expand in flesh while the remaining jacket still prevented lead fouling in the barrel. For metallic silhouette purposes, JSP is roughly splitting the difference between FMJ and JHP. It gives more penetration than JHP but has more stopping power than the FMJ.

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JHP - Jacketed Hollow Point - Soon after the invention of the JSP, Woolwich Arsenal in Great Britain experimented with this design even further by forming a hole or cavity in the nose of the bullet while keeping most of the exterior profile intact. These bullets could theoretically deform even faster and expand to a larger diameter than the JSP.

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Glaser Safety Slug - The Glaser Safety Slug dates back to the early 1970s. The inventor, Colonel Jack Cannon named it for his friend Armin Glaser. Over the years, the projectiles have evolved from crude, hand-produced examples to massproduction; however, the basic concept has remained the same: copper jackets filled with bird shot and covered by a crimped polymer endcap. Upon impact with flesh, the projectile fragments, with the birdshot spreading like a miniature shotgun pattern. The standard 'Blue' Glaser uses a rather fine birdshot which only gives 5 to 6 inches (130–150 mm) of penetration in flesh. The 'Silver' Glaser adds another 1 to 2 inches (30–50 mm) of penetration with the use of slightly larger birdshot. Due to the much reduced penetration in flesh, some have theorized that the Glaser would be ideal where over-penetration of a projectile could be hazardous to bystanders. For instance, the Glaser may be stopped by an upraised arm. However, for the same reasons, the Glaser’s terminal performance can vary dramatically, producing impressive successes and equally spectacular failures depending on the angle at which the target is struck. Glancing hits on hard surfaces will result in fragmentation, reducing the risk of ricochets. However, the Glaser can penetrate barriers such as drywall, plywood, and thin sheet metal if struck directly.

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The Hague Accords - The Hague Accords ban the use of expanding projectiles against the military forces of other nations. Some countries accept this as a blanket ban against the use of expanding projectiles against anyone, while others[1] use JSP and HP against non-military forces such as terrorists and criminals.

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12 gauge/70 mm shotgun ammunition. They are listed from largest to smallest, separating the list into non-armor piercing and armor piercing types. The capacities are based on a 70 mm length hull. 000 Buck - 8 lead pellets (0.36 in/9.1 mm) 00 Buck - 9 lead pellets (0.33 in/8.4 mm) 0 Buck - 12 lead pellets (0.32 in/8.1 mm) 1 Buck - 16 lead pellets (0.30 in/7.6 mm) 4 Buck - 27 lead pellets (0.24 in/6.1 mm) QB 8 - 8 pellets (Armor Piercing) - Quadrangle Buck is made from a steel cylinder cut into two layers of four pie-shaped pieces per layer. The numerous sharp edges enhance penetration at short ranges; however, the light weight and poor ballistic shape limits its effective range. Flechettes - 32 flechettes - Flechettes are essentially small steel darts with tiny fins swaged into the rear. Slug - Slugs may be made of solid lead, copper, or a composite. Slugs are stabilized in flight by rifling in the gun tube, by means of integral rifling, or finstabilized. Solid or hollow-point slugs are available but, due to the relatively low velocity, hollow-point slugs have relatively low expansion.

Baton - Rubber batons. Used for training.

[edit] Calibers Ammunition types are listed numerically. •

.22 Long Rifle or .22LR cartridge is often used for target shooting and the hunting of small game such as squirrel, although because of its small size, self-defense handguns chambered in .22 rimfire (despite its name, it is often fired in pistols and revolvers in addition to rifles), though far less effective than centerfire handguns, can be concealed in situations where a larger handgun could not. It is the most commonly fired small arms cartridge, primarily because rimfire ammunition is much cheaper to produce than centerfire and because the recoil from the small .22" projectile being accelerated to relatively low velocities is very mild.

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9 mm can refer to a variety of pistol cartridges, but most commonly it means the 9x19mm Parabellum round. It is used in a variety of semi-automatic handguns and submachine guns.

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.30 US Carbine - In 1940, the US Army's Ordnance Department approached Winchester with a light rifle concept. This was to bridge the difference between the .45 ACP and the .30-06. For the cartridge, Winchester recommended a rimless version of their .32 Winchester Self-Loading sized down for 0.308 inches (7.8 mm) projectiles. The resulting cartridge tossed a 110-grain (7.1 g) projectile at nearly 2,000 feet per second (610 m/s) from a carbine-length barrel.

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.300 Whisper subsonic - Made by necking-up the .221 Remington Fireball case to 0.308 inches (7.8 mm) and using a 240-grain (16 g) Sierra MatchKing, this cartridge will fit and feed from 5.56x45mm NATO magazines. The Whisper is subsonic with about as much power and weight as .45 ACP, but in a thinner bullet which dramatically increases armor penetration.

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.300 Winchester Magnum - A long range sniping round, it is favored by US Navy SEALS and the German Bundeswehr. While not in the same class as the .338 Lapua, it has roughly the same power as 7 mm Remington Magnum, and easily exceeds the performance of 7.62x51mm NATO.

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.308 Winchester - the commercial name of a centerfire cartridge based on the military 7.62x51mm NATO round. Two years prior to the NATO adoption of the 7.62x51mm NATO T65 in 1954, Winchester (a subsidiary of the Olin Corporation) branded the cartridge and introduced it to the commercial hunting market as the .308 Winchester. Winchester's Model 70 and Model 88 rifles were subsequently chambered for the new cartridge. Since then, the .308 Winchester has become the most popular short-action big-game hunting cartridge worldwide.

It is also commonly used for civilian targets, military sniping and police sharpshooting. •

.338 Lapua (8.6x70mm or 8.58x71mm) - Originally designed as a long range sniping cartridge to bridge the ballistic gap between the .300 Winchester Magnum and the .50 BMG. It is a specialized rimless centerfire cartridge developed for sniper rifles. The .338 Lapua is a dual purpose anti-personnel and anti-materiel round for long-range shooting. In addition, with its increased popularity it is being used by big-game hunters and long-range competition shooters.

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.338 Whisper subsonic - Made by necking-up the 7 mm Remington BenchRest case to 0.338 inches (8.6 mm) and using a 300-grain (19 g) Sierra MatchKing, this cartridge will fit and feed from 7.62x51mm NATO magazines.

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.357 Magnum - Using a lengthened and strengthened version of the .38 Special case, the .357 Magnum was rapidly accepted by hunters and law enforcement. At the time of its introduction, it was claimed to easily pierce the body panels of automobiles and crack engine blocks.

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.357 SIG - Designed to produce .357 Magnum revolver ballistics in a self-loading pistol, the .357 SIG is roughly a .40 S&W case necked down to 0.355 inches (9.0 mm).

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.376 Steyr - Roughly a shortened 9.3x64mm Brenneke case necked up for 0.375 inches (9.5 mm) projectiles. The cartridge is loaded to give performance approaching that of the .375 Holland & Holland.

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.40 S&W - Roughly a shorter cased version of the 10x25mm Norma.

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.40 S&W subsonic - Roughly a shorter cased version of the 10x25mm Norma, this round loses about 20% of its energy when subsonic. This round is a step up in power from the 9x19mm subsonic, and has beaten out the parent 10x25mm subsonic in popularity.

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.408 Chey Tac - is based on the .400 Taylor Magnum, which is based on a modified .505 Gibbs, necked down to 0.408 inches (10.36 mm).

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.44 Magnum - A high powered pistol cartridge designed primarily for hunting.

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.440 Cor-bon - The .440 Cor-bon is derived by necking down a .50 Action Express case down to accept the same .429-inch (10.9 mm) projectiles used in .44 Magnum cartridges. The 240-grain (16 g) .429-inch (10.9 mm) projectile has equal sectional density to the 325-grain (21.1 g) .500-inch (12.7 mm) of the .50 AE. However, with equal powder charges, the .440 Cor-bon can launch the 240grain (16 g) projectile much faster than the 325 grains (21.1 g) projectile from the .50 AE. This equals greater energy and penetration against hard and soft targets.

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.45 ACP - The standard US pistol round for about a century. Typical .45 ACP loads are subsonic, making them ideal for suppressed weapons.

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.45 SAA - A more powerful .45 caliber round with a lengthened shell designed for the Colt Single Action Army. Other .45 caliber single action revolvers also chamber this round.

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.454 Casull - A very high powered pistol cartridge designed for taking the largest game animals.

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.45-70 Government - Adopted by the US Army in 1873 as their standard service rifle cartridge. Most commercial loadings of the cartridge are constrained by the possibility that someone may attempt to fire a modern loading in one of the 1873vintage rifles. However, current production rifles from Marlin, Ruger, and Browning can accept pressures nearly twice as high as the original black powder specs.

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.50 Action Express (AE) - A very high powered pistol cartridge, exceeding the .44 Magnum, the cartridge's combination of high velocity and mass results in very favorable penetration characteristics against hard cover and certain types of body armor.

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4.6x30mm H&K - H&K's answer to the 5.7x28mm FN. Based on H&K's experimental 4.6x36mm cartridge for the HK36 ACR in the early 1970s, even retaining its unique Löffelspitz (spoon-nose) projectile.

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4.73x33mm H&K caseless - This revolutionary round, developed for Heckler & Koch G11, encases the bullet in a combustible material. There is no brass holding the cartridge together and the "powder" is completely burned upon firing.

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5.45x18mm Soviet - Similar to a necked down 6.35x16mm Browning (.25 ACP) and producing exterior ballistics equal to a .22 rimfire, 5.45x18mm cartridge possesses an impressive ability to defeat body armor.

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5.45x39mm Soviet - The Soviet's response to the 5.56x45mm NATO cartridge.

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5.56x45mm Steyr Flechette - Introduced for the US Army's ACR trials, the Steyr cartridge uses a plastic case with a small caliber flechette pulled by a 5.56 mm diameter sabot. The flechette is launched at a high velocity and the narrow projectile offers excellent penetration.

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5.56x45mm NATO - Adopted by the US military in the 1960s, it later became the NATO standard assault rifle cartridge in the early 80s, displacing the 7.62x51mm. It is a military adaptation of the .223 Remington, a common cartridge for varminting and small game hunting.

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5.7x28mm FN - The small high velocity cartridge appears much like a miniature rifle round. The 5.7 mm FN cartridge has amazing armor penetration due to its small projectile size and speed, yet has much less recoil than many pistol rounds.

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7 mm Remington Magnum - A long-range hunting cartridge.

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7.62x39mm - The standard Soviet/ComBloc rifle cartridge from the mid-1940s to the mid-1970s, it is easily one of the most widely distributed cartridges in the world due to the distribution of the ubiquitous Kalashnikov AK-47 series.

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7.62x42mm - Outwardly similar to the Nagant revolver cartridge, the 7.62x42mm Soviet's case contains not only propellant and a projectile, but a piston sandwiched between the two. When the propellant is ignited, the expanding gas presses the piston forward to expel the projectile. However, the piston remains trapped inside the case, effectively sealing off the escape of propellant gas. The lack of expelled gas and a subsonic projectile results in no firing signature other than the mechanism of the parent weapon. The 7.62 × 42 mm is credited with a maximum effective range of 50 m, and the SP-4 armor-piercing cartridge can only defeat a helmet or body armor out to 25 m.

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7.62x51mm NATO - This was the standard NATO rifle round until its replacement by the 5.56x45mm. It is currently NATO's standard sniper rifle and medium machine gun cartridge. In the 1950s it was the standard NATO cartridge for rifles, but recoil and weight proved problematic for the new battle rifle designs such as the FN FAL.

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.30-06, (7.62x63mm) was the standard US Army rifle cartridge for the first half of the 20th century. It is a full-power rifle cartridge suitable for hunting most North American game.

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7.62x54mmR - The standard Russian rifle round from the 1890s to the mid-1940s. The "R" stands for rimmed. The 7.62x54R rifle cartridge is a Russian design dating back to 1891. Originally designed for the Mosin-Nagant rifle, it was used during the late Tsarist era and throughout the Soviet period, in machine guns and rifles such as the SVT-40. The Winchester Model 1895 was also chambered for this cartridge per a contract with the Russian government. It is still in use by the Russian military in the Dragunov and other sniper rifles and some machine guns. The round is colloquially known as the "7.62 Russian". The name is sometimes confused with the "7.62 Soviet" round, which refers to the 7.62 × 39 cartridge used in the SKS and AK-47 rifles.

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7.65x17mm Browning SR (.32 ACP) - A very small pistol round. However, it was the predominant police service cartridge in Europe until the mid-1970s. The "SR" stands for semi-rimmed, meaning cartridge case has small rim and usual groove.

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7.92x57mm Mauser - The standard German service rifle cartridge from 1888 to 1945, the 7.92x57mm (aka 8 mm Mauser) has seen wide distribution around the globe through commercial, surplus, and military sales.

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9x19mm Parabellum - Invented for the German military at the turn of the century, the wide distribution of the 9x19mm Parabellum cartridge made it the logical choice for the NATO standard pistol and SMG round.

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9x21mm Russian - The 9x21mm Russian cartridge is roughly a lengthened version of the 9x18mm Makarov/PMM.

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9x23mm Winchester - Roughly a 9x19mm case lengthened by 4 mm, the 9x23mm Winchester has its roots in IPSC competition shooting. John Ricco of CP Bullets had developed the '9x23mm Super' case as an alternative to the .38 Super ACP, whose cases varied dramaticly in strength. The .38 Super case also has the disadvantage of a vestigial semi-rim, which can interlock in magazines. Not to be confused with the externally similar 9x23mm Bergmann-Bayard (aka 9 mm Largo), Ricco's case could be safely loaded to nearly double the chamber pressure of the older cartridges. Since Olin/Winchester produced the cases for Ricco, they saw the commercial potential for using the case in a loaded cartridge. Unfortunately, Olin/Winchester tried to cut Ricco out of his potential royalties from sale of the new 9x23mm Winchester. The resulting lawsuit (won by Ricco) and the poor marketing of 9x23mm pistols by Colt has led to tepid commercial acceptance. Despite these troubles, the 9x23mm Winchester comes closer to the goal of matching .357 Magnum ballistics than the more popular .357 SIG.

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9x30mm Grom - The 9x30mm Grom (Thunder) is roughly similar in dimensions and performance to the commercially unsuccessful 9 mm Winchester Magnum.

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9x39mm Soviet subsonic - The 9x39mm Soviet is roughly a 7.62x39mm Soviet case necked up for a heavy 9 mm rifle projectile. There are competitive loadings from Nikolai Zabelin and Yuri Folov, each optimized for specific roles.

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10x25mm Norma - Originally designed for the ill-fated Bren Ten pistol, the cartridge gained another lease on life when it was briefly promoted by the US FBI.

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.50 BMG (12.7x99mm BMG) - Originally designed to pierce tank armor in the First World War, the cartridge still serves an anti-materiel round against light armor. It is used in heavy machine guns and high-powered sniper rifles. Such rifles are intended for destroying military matériel such as sensitive parts of grounded aircraft and armored transports. Civilian shooters use them for longdistance target-shooting.

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14.5x114mm - Also originally designed to pierce tank armor, now used in KPV heavy machine gun.

[edit] History The original cartridge for military small arms dates from 1586. It consisted of a charge of powder and a bullet in a paper tube. Thick paper is still known as cartridge paper from its use in these cartridges. This cartridge was used with the muzzle-loading military firearm, the base of the cartridge being ripped or bitten off by the soldier, the powder poured into the barrel, and the bullet then rammed home. Before the invention of the firelock or flintlock, about 1635, the priming was originally put into the pan of the wheellock and snaphance muskets from a flask containing a fine-grained powder called serpentine powder. The evolving nature of warfare required a firearm which could be fired more rapidly, resulting in the flintlock musket (and later the Baker rifle), in which the pan was covered by furrowed steel. This was struck by the flint and fired the weapon. In the course of loading a pinch of powder from the cartridge would be placed into the pan as priming, before the rest of the cartridge was rammed down the barrel, providing charge and wadding. Later developments rendered this method of priming unnecessary, as, in loading, a portion of the charge of powder passed from the barrel through the vent into the pan, where it was held by the cover and hammer. The next important advance in the method of ignition was the introduction of the copper percussion cap. This was only generally applied to the British military musket (the Brown Bess) in 1842, a quarter of a century after the invention of percussion powder and after an elaborate government test at Woolwich in 1834. The invention which made the percussion cap possible was patented by the Rev. A. J. Forsyth in 1807, and consisted of priming with a fulminating powder made of potassium chlorate, sulphur and charcoal, which exploded by concussion. This invention was gradually developed, and used, first in a steel cap, and then in a copper cap, by various gunmakers and private individuals before coming into general military use nearly thirty years later. The alteration of the military flint-lock to the percussion musket was easily accomplished by replacing the powder pan by a perforated nipple, and by replacing the cock or hammer which held the flint by a smaller hammer with a hollow to fit on the nipple when released by the trigger. On the nipple was placed the copper cap containing the detonating composition, now made of three parts of potassium chlorate, two of fulminate of mercury and one of powdered glass. The detonating cap thus invented and adopted, brought about the invention of the modern cartridge case, and rendered possible the general adoption of the breech-loading principle for all varieties of rifles, shotguns and pistols. This greatly streamlined the reloading procedure and paved the way for semi- and fully-automatic firearms. But this big leap forward came at a price. It introduced an extra component into each round – the cartridge case - which had to be removed before the gun could be reloaded.

While a flintlock, for example, is immediately ready to be reloaded once it has been fired, adopting brass cartridge cases brought in the problem of extraction and ejection. The mechanism of a modern gun not only must load and fire the piece but also must remove the spent case, which may require just as many moving parts. Many malfunctions involve this process, either through failure to extract a case properly from the chamber or by allowing it to jam the action. Nineteenth-century inventors were reluctant to accept this added complication and experimented with a variety of self-consuming cartridges before finally accepting that the advantages of brass cases far outweighed their one drawback.

[edit] Integrated paper cartridges

Chassepot paper cartridge (1866). The first integrated cartridge, was developed in Paris in 1808 by the Swiss gunsmith Jean Samuel Pauly in association with French gunsmith François Prélat. Pauly created the first fully self-contained cartridges:[2] the cartridges incorporated a copper base with integrated mercury fulminate primer powder (the major innovation of Pauly), a paper casing and a round bullet.[3] The cartridge was loaded through the breech and fired with a needle. The needle-activated central-fire breech-loading gun would become a major feature of firearms thereafter.[4] Pauly made an improved version which was protected by a patent on 29 September 1812.[2] Probably no invention connected with firearms has wrought such changes in the principle of gun construction as those effected by the "expansive cartridge case". This invention has completely revolutionized the art of gunmaking, has been successfully applied to all descriptions of firearms, and has produced a new and important industry: that of cartridge manufacture. Its essential feature is the preventing gas escaping the breech when the weapon is fired, by means of an expansive cartridge case containing its own means of ignition. Previous to this invention shotguns and sporting rifles were loaded by means of powder flasks and shot flasks, bullets, wads and copper caps, all carried separately. One of the earliest efficient modern cartridge case was the pin-fire cartridge, developed by French gunsmith Casimir Lefaucheux in 1836.[5]. It consisted of a thin weak shell made of brass and paper which expanded by the force of the explosion, fitted perfectly into the barrel, and thus formed an efficient gas check. A small percussion cap was placed in the middle of the base of the cartridge, and was exploded by means of a brass pin projecting from the side and struck by the hammer. This pin also afforded the means of extracting the cartridge case. This cartridge was introduced in England by Lang, of Cockspur Street, London, about 1855. Later in 1846, M.Houiller, another Paris gunsmith, improved on the system by introducing a fully metallic cartridge in 1847.[6]

A diagram of a Dreyse needle gun cartridge, showing the paper cartridge case, the sabot, and acorn-shaped bullet. As a result of the relatively low pressures involved, cartridges used in modern shotguns have changed very little since the invention of the center-fire primer. The only changes are that the cases may be made of paper, plastic, and/or metal; the wadding between powder and shot is now made of modern materials; and the end of the cartridge case is more precisely fitted to the breech chamber, which ranges in modern shotguns from .410inch (10.4 mm) bore to various gauges, 10 gauge being the largest still used in modern shoulder-held shotguns (smaller gauges have industrial uses). Gauge is measured by the number of equal-sized balls that can be formed from a pound of pure lead; a 12-gauge shotgun has a bore of 0.729 inches (18.5 mm), which is the diameter of a 1⁄12-pound (38 g) ball of lead; a 10 gauge fits one of 10 balls produced from a pound (460 g) of lead (.775 inches/19.7 millimetres bore). Rifle cartridges, on the other hand, have undergone significant changes as the pressures involved have increased. In the case of military rifles the breech-loading cartridge case was first adopted in principle by the Prussians about 1841 in the needle-gun breechloader. In this a conical bullet rested on a thick wad, behind which was the powder, the whole being enclosed in strong lubricated paper. The detonator was in the hinder surface of the wad, and fired by a needle driven forward from the breech, through the base of the cartridge and through the powder, by the action of a spiral spring set free by the pulling of the trigger. In the American Civil War (1861-65) a breechloading rifle, the Sharps, was introduced and produced in large numbers. It could be loaded with either a ball or a paper cartridge. After that war many were converted to the use of metal cartridges. The development by Smith and Wesson (amongst many others) of revolver handguns that used metal cartridges helped to establish cartridge firearms as the standard in the USA by the 1870s although many continued to use percussion revolvers well after that.

[edit] Full metal cartridges

(From Left to Right): A .577 Snider cartridge (1867), a .577/450 Martini-Henry cartridge (1871), a later drawn brass .577/450 Martini-Henry cartridge, and a .303 British Mk VII SAA Ball cartridge.

French Army Fusil Gras mle 1874 metallic cartridge. The first commercially successful all-metal cartridges were rimfire cartridges. The first of these was the .22 BB Cap, introduced around 1845. This was followed by the .22 Short in 1857. Larger caliber rimfires were soon introduced. Some of these were used in the American Civil War, including the .44 Henry and 56-56 Spencer. However, the large rimfires were soon replaced by centerfire cartridges, which could safely handle higher pressures. In 1867 the British war office adopted the Eley-Boxer metallic central-fire cartridge case in the Enfield rifles, which were converted to Snider-Enfield breech-loaders on the Snider principle. This consisted of a block opening on a hinge, thus forming a false breech against which the cartridge rested. The priming cap was in the base of the cartridge, and was discharged by a striker passing through the breech block. Other European powers adopted breech-loading military rifles from 1866 to 1868, with paper instead of metallic cartridge cases. The original Eley-Boxer cartridge case was made of thin coiled brass occasionally these cartridges could break apart and jam the breech with the unwound remains of the casing upon firing. Later the solid-drawn, central-fire cartridge case, made of one entire solid piece of tough hard metal, an alloy of copper, with a solid head of thicker metal, has been generally substituted.

The 8 mm Lebel ammunition, developed in 1886, the first smokeless gunpowder cartridge to be made and adopted by any country. Central-fire cartridges with solid-drawn metallic cases containing their own means of ignition are almost universally used in all modern varieties of military and sporting rifles and pistols. Around 1870, machined tolerances had improved to the point that the cartridge case was no longer necessary to seal a firing chamber. Precision-faced bolts would seal as well, and could be economically manufactured.

[edit] Reloading Some shooting enthusiasts reload their spent brass cartridges. By using a press and a set of dies, one can reshape, deprime, reprime, recharge the case with gunpowder, and seat

and crimp a new bullet. One can do this at about half the cost of purchasing factory ammunition. It also allows one to use different weights and shapes of bullets, as well as varying the powder charge which affects accuracy and power. Enthusiasts usually only reload boxer primed cartridges as the process is more easily automated than berdan priming. See also: Handloading

[edit] Caseless ammunition Main article: Caseless ammunition In 1989, Heckler & Koch, a prominent German firearms manufacturer, began making press releases about the G11 assault rifle, which shot a 4.73x33 square caseless round. The round was mechanically fired, with an integral primer. In 1993 Voere of Austria began selling a gun and caseless ammunition. Their system used a primer, electronically-fired at 17.5 ± 2 volts. The upper and lower limits prevent fire from either stray currents or static electricity. The direct electrical firing eliminates the mechanical delays associated with a striker, reducing reaction time (lock time), and allowing for easier adjustment of the rifle trigger. In both cases, the "case" was molded directly from solid nitrocellulose, which is itself relatively strong and inert. The bullet and primer were glued into the propellant block.

[edit] Trounds Main article: Dardick tround The Tround (Triangular Round) was a unique type of cartridge designed in 1958 by David Dardick, for use in specially designed Dardick 1100 and Dardick 1500 openchamber firearms. As their name suggests, Trounds were triangular in cross-section, and were made of plastic or aluminium, with the cartridge completely encasing the powder and projectile. The Tround design was also produced as a cartridge adaptor, to allow conventional .38 Special and .22 Long Rifle cartridges to be used with the Dardick firearms.

[edit] Blank ammunition Main article: Blank (cartridge)

Blank cartridges: • •

7.62x51mm NATO (left) 9x19mm Parabellum (right).

A blank is a charged cartridge that does not contain a projectile — the opening where the projectile would be held is crimped shut or sealed with some material that will disperse rapidly upon leaving the barrel, in order to contain the propellant. This sealing material can still potentially cause harm at extremely close range. Blanks are used in training, but do not always cause a weapon to behave in an identical way to when using live ammunition; recoil will almost always be far weaker, and some automatic weapons will only cycle correctly when the weapon is fitted with a blank-firing adaptor to confine gas pressure within the barrel in order to operate the gas system. Blanks may also be used to launch a rifle grenade, although later systems used a "bullet trap" design that captures a bullet from a conventional round, speeding deployment. This also negates the risk of mistakenly firing a live bullet into the rifle grenade, causing it to explode instead of propelling it forward. Blanks may also be used in dedicated launchers for propelling a grapnel, rope line or flare, or for a training lure for training gun dogs. The propellant cartridges used in a heavier variety of nail gun are essentially rimfire blanks.

[edit] Drill rounds

23x152mm cartridge, drill round

Drill rounds are inert versions of cartridges used for education and practice during military training. Other than the lack of propellant, they are the same size as normal cartridges and will fit into the mechanism of a weapon in the same way as a live cartridge. To distinguish them from live rounds they are marked distinctively. Several forms of markings may be used; eg setting coloured flutes in the cartridge, drilling holes through the cartridge, colouring the bullet or cartridge, or a combination of these. In the case of centrefire drill rounds the primer will often be absent, its mounting hole in the base left open. Because they are mechanically identical to live rounds, which are intended to be loaded once, fired and then discarded, drill rounds have a tendency to become significantly worn and damaged with repeated passage through magazines and firing mechanisms, and need to be frequently inspected to ensure they are not so degraded as to become unusable - for example the casings can become torn or misshapen and snag on moving parts, or the bullet can become separated and stay in the breech when the cartridge is ejected.

[edit] See also Wikimedia Commons has media related to: Pistol and rifle cartridges

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Ammunition Ammunition box Antique guns Bullet List of handgun cartridges List of rifle cartridges Nitrocellulose Percussion cap Simunition Table of pistol and rifle cartridges by year

Gun From Wikipedia, the free encyclopedia

Jump to: navigation, search This article may require cleanup to meet Wikipedia's quality standards. Please improve this article if you can. (April 2008) This article is about the projectile weapon. For other uses, see Gun (disambiguation). In military parlance, a gun is a muzzle or breech-loaded projectile-firing weapon. There are various definitions depending on the nation and branch of service. A "gun" may be distinguised from other firearms in being a crew served weapon such as a howitzer or

mortar, as opposed to a small arm like a rifle or pistol, but there are exceptions, such as the USAF's GUU5/P. At one time, Land-based Artillery tubes were called Cannon and Sea-based Naval Cannon were called Guns. The term "gun" morphed into a generic term for any tube launched projectile firing weapon used by sailors including boarding parties and Marines. In modern parlance, a gun is a projectile weapon using a hollow, tubular barrel with a closed end—the breech—as the means for directing the projectile as well as other purposes—an expansion chamber for propellant, stabilizing the projectile's trajectory, aiming, etc.—and assumes a generally, flat trajectory for the projectile. The generic form of a trigger-initiated, hand-held, and hand-directed tool with an extending bore has additionally been applied to implements resembling guns in either form or concept. Examples of this application include items such as staple guns, nail guns, and glue guns. Occasionally, this tendency is ironically reversed, such as the case of the American M3 submachine gun which carries the nickname "Grease Gun". The projectile may be a simple, single-piece item like a bullet, a casing containing a payload like a shotshell or explosive shell, or complex projectile like a sub-caliber projectile and sabot. The propellant may be air, an explosive solid, or an explosive liquid. Some variations like the Gyrojet and certain other types combine the projectile and propellant into a single item. Most guns are described by the type of barrel used, the means of firing, the purpose of the weapon, the caliber, or the commonly accepted name for a particular variation. Barrel types include rifled—a series of spiraled grooves or angles within the barrel— when the projectile requires an induced spin to stabilize it and smoothbore when the projectile is stabilized by other means or is undesired or unnecessary. Typically, interior barrel diameter and the associated projectile size is a means to identify gun variations. Barrel diameter is reported in several ways. The more conventional measure is reporting the interior diameter of the barrel in decimal fractions of the inch or in millimeters. Some guns—such as shotguns—report the weapon's gauge or—as in some British ordnance— the weight of the weapon's usual projectile.

Types of guns

Colt Python .357 Magnum revolver

Marlin Model 1894C — a carbine in .357 Magnum

Military firearms •

Long gun o Arquebus o Blunderbuss o Musket  Musketoon  Wall gun  Grenade launcher o Personal defense weapon o Rifle  Lever action rifle  Bolt action rifle  Assault rifle  Battle rifle  Carbine  Service rifle  Sniper rifle o Shotgun  Combat shotgun  Semi-automatic shotgun o Submachine gun o Tu Huo Qiang

Machine guns • • •

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Gatling gun Mitrailleuse Machine gun o General-purpose machine gun o Heavy machine gun o Light machine gun o Medium machine gun o Squad automatic weapon Minigun .50 BMG Submachine gun Metal storm

Autocannon • •

Autocannon Chain gun

Artillery guns •

Artillery gun o Carronade o Howitzer

Tank guns • •

Tank gun .50 BMG

Hunting guns • • • • •

Elephant gun Express rifle Shotgun Muzzleloader Breechloader

Guns for training and entertainment • • • • •

Airsoft gun BB gun Paintball gun Spud gun Water gun

Gunshot residue From Wikipedia, the free encyclopedia

Jump to: navigation, search Gunshot residue (GSR) are principally composed of burnt and unburnt particles from the explosive primer, the propellant, as well as components from the bullet, the cartridge case and the firearm used. There are authors who use other definitions, such as cartridge discharge residue (CDR) or firearm discharge residue (FDR).

In 1971 Boehm presented some micrographs of GSR particles found during the examination of bullet entrance holes using a scanning electron microscope. If the scanning electron microscope is equipped with an X-ray microanalysis, the chemical elements present in such particles, mainly lead, antimony and barium, can be identified. In 1979 Wolten et al. proposed a classification of GSR following compositional criteria, morphology and size. Four compositions were considered “characteristic”: lead, antimony and barium; barium, calcium and silicon; antimony and barium. The authors proposed some rules about the chemical elements which could also be present in these particles. Wallace and McQuillan published a new classification of the GSR particles in 1984. They called “unique” particles the ones containing lead, antimony and barium, or the ones containing antimony and barium. Also for Wallace and McQuillan in these particles only some chemical elements could be present. In the latest ASTM Standard Guide for GSR analysis by Scanning Electron Microscopy/Energy Dispersive X-ray Spectrometry particles containing lead, antimony and barium, and respecting some rules related to the morphology and to the presence of other elements are considered characteristic of GSR. The most definitive method to determine if a particle is characteristic of or consistent with GSR is by its elemental profile. An approach to the identification of particles characteristic of or consistent with GSR is to compare the elemental profile of the recovered particulate with that collected from case-specific known source items, such as the recovered weapon, cartridge cases or victim-related items whenever necessary. Particle analysis by scanning electron microscope equipped with an X-ray microanalysis can be the most powerful tool for forensic scientists to determine the proximity to a discharging firearm and/or the contact with a surface exposed to GSR (firearm, spent cartridge case, target hole), if proper attention is paid to avoid secondary gunshot residue transfer from officers onto subjects or items to be tested for GSR, and to avoid contamination in the laboratories. Organic gunshot residue can be analysed by analitical techniques such as Chromatography, Capillary Electrophoresis, Mass Spectrometry.

Physics of firearms From Wikipedia, the free encyclopedia

Jump to: navigation, search From the viewpoint of physics (dynamics, to be exact), a firearm, as for most weapons, is a system for delivering maximum destructive energy to the target with minimum delivery of energy on the shooter. The momentum delivered to the target however cannot be any

more than that (due to recoil) on the shooter. This is because the momentum imparted to the bullet is equal to that imparted to the gun-shooter system.

Firearm energy efficiency From a thermodynamic point of view, a firearm is a special type of piston engine, or in general heat engine where the bullet has a function of piston. The Energy conversion efficiency of a firearm strongly depends on its construction, especially on its caliber and barrel length. However, for illustration, here is the energy balance of a typical small firearm for .300 Hawk ammunition [1] : • • • • •

Projectile motion 32% Barrel friction 2% Hot gases 34% Barrel heat 30% Unburned propellant 1%.

which is comparable with a typical piston engine. Higher efficiency can be unachieved in longer barrel firearms because they have better volume ratio. However, the efficiency gain is less than corresponding to the volume ratio, because the expansion is not truly adiabatic and burnt gas becomes cold faster because of exchange of heat with the barrel. Large firearms (such as cannons) achieve smaller barrel-heating loss because they have better volume-to-surface ratio. High barrel diameter is also helpful because lower barrel friction is induced by sealing compared to the accelerating force. The force is proportional to the square of the barrel diameter while sealing needs are proportional to the perimeter by the same pressure.

[edit] Force Assuming the gun and shooter are at rest, the force on the bullet is equal to that on the gun-shooter. This is due to Newton's third law of motion (For every action, there is an equal and opposite reaction). Consider a system where the gun and shooter have a combined mass M and the bullet has a mass m. When the gun is fired, the two systems move away from one another with new velocities V and v respectively. But the law of conservation of momentum states that the magnitudes of their momenta must be equal:

Since force equals the rate of change in momentum and the initial momenta are zero, the force on the bullet must therefore be the same as the force on the gun/shooter. Hollywood depictions of firearm victims being thrown through plate-glass windows are inaccurate. Were this to be the case, the shooter would also be thrown backwards with equal force. Gunshot victims frequently fall or collapse when shot; this is less a result of

the momentum of the bullet pushing them over, but is primarily caused by physical damage or psychological effects, perhaps combined with being off-balance. This is not the case if the victim is hit by heavier projectiles such as 20 mm cannon shell, where the momentum effects can be enormous; this is why very few such weapons can be fired without being mounted on a weapons platform or involve a recoilless system (e.g. a recoilless rifle).

[edit] Velocity From Eq. 1 we can write for the velocity of the gun/shooter: V = mv/M. This shows that despite the high velocity of the bullet, the small bullet-mass to shooter-mass ratio results in a low recoil velocity (V) although the force and momentum are equal.

[edit] Kinetic Energy However, the smaller mass of the bullet, compared that of the gun-shooter system, allows significantly more kinetic energy to be imparted to the bullet than to the shooter. The kinetic energy for the two systems are for the gun-shooter system and the bullet. The energy imparted to the shooter can then be written as:

for

If we now write for the ratio of these energies we have:

The ratio of the kinetic energies is the same as the ratio of the masses (and is independent of velocity). Since the mass of the bullet is much less than that of the shooter there is more kinetic energy transferred to the bullet than to the shooter. Once discharged from the weapon, the bullet's energy decays throughout its flight, until the remainder is dissipated by colliding with a target (e.g. deforming the bullet and target).

[edit] Transfer of Energy When the bullet strikes, its high velocity and small frontal cross-section means that it will exert large stresses in any object it hits. This usually results in it penetrating any soft object, such as flesh. The energy is then dissipated in the wound track formed by the passage of the bullet. See terminal ballistics for a fuller discussion of these effects. Bulletproof vests work by dissipating the bullet's energy in another way; the vest's material, usually Aramid (Kevlar or Twaron), works by presenting a series of material

layers which catch the bullet and spread its imparted force over a larger area, hopefully bringing the round to a stop before it can penetrate into the body. While the vest can prevent a bullet from penetrating, the wearer will still be affected by the kinetic energy of the bullet, which can produce serious internal injuries.

Trajectory From Wikipedia, the free encyclopedia

Jump to: navigation, search For other uses, see Trajectory (disambiguation). A trajectory is the path a moving object follows through space. The object might be a projectile or a satellite, for example. It thus includes the meaning of orbit - the path of a planet, an asteroid or a comet as it travels around a central mass. A trajectory can be described mathematically either by the geometry of the path, or as the position of the object over time. In control theory a trajectory is a time-ordered set of states of a dynamical system (see e.g. Poincaré map). In discrete mathematics, a trajectory is a sequence of values calculated by the iterated application of a mapping f to an element x of its source.

Vaporific effect From Wikipedia, the free encyclopedia

(Redirected from Vaporific Effect) Jump to: navigation, search Vaporific effect is a flash fire resulting from the impact of high velocity projectiles with metallic objects. Impacts produces particulate matter originating from either the projectile, the target, or both. Particles heated from the force of impact can burn in the presence of air (oxidizer). An explosion can result from the mixture of metal-dust and air, the resulting dust explosion causing significant overpressure within metallic enclosures (aircraft, vehicles, metallic enclosures, etc). The vaporific effect is particularly pronounced when these enclosures are constructed of pyrophoric metals (metals that react upon contact air, such as aluminium, magnesium, or their alloys. Depleted uranium is a pyrophoric material used in kinetic penetrator ammunition.