Polymer-cased ammunition
Encyclopedia
Overview
A plastic cylinder makes up the body of the cartridge. Starting from the back of the interior of the cartridge: The primer material. A priming method for rimfire cartridges is disclosed in which a propellant solution is disposed adjacent a centrifugally located primer material in a rimfire cartridge. The solvent is then evaporated to leave a propellant film near the primer material in order to provide slower, more uniform ignition to thereby allow use of propellant powders which would otherwise be too fast or too sensitive. Then comes the main charge of smokeless powder. Next is the projectile/projectiles. This can be a variety of things, from multiple shot (bird shot), a single-bullet projectile, or a saboted flechette, and then, if necessary, the sabotSabot
A sabot is a device used in a firearm or cannon to fire a projectile, such as a bullet, that is smaller than the bore diameter, or which must be held in a precise position. The term is also applied to a battery stub case, a device used similarly to make a small electrical battery usable in a...
/sabots. Sabots are a piece of plastic that fits around the projectile. The plastic fits snugly against the rifling of the barrel and thus makes the cartridge more accurate if the projectile does not fit snugly against the rifling.
Examples
The Steyr ACRSteyr ACR
The Steyr ACR was a prototype flechette-firing assault rifle built for the US Army's Advanced Combat Rifle program of 1989/90. Although the Steyr design proved effective, as did most of the weapons submitted, the entire ACR program ended with none of the entrants achieving performance 100% better...
is the most notable user of polymer cased ammunition. It is a bullpup
Bullpup
Bullpups are firearm configurations in which the action is located behind the trigger group and alongside the shooter's face, so there is no wasted space for the buttstock as in conventional designs. This permits a shorter firearm length for the same barrel length for improved maneuverability, and...
, rimfire rifle, that shoots a 5.56 X 45 mm flechette cartridge. The muzzle velocity is 4,757 ft/s. The flechette design allows it to retain much of its velocity and kinetic energy as it travels through the air; making it shoot very flat. This allows the rifle to be "sighted in" at 50 yards and still maintain close to the same point of impact out to a range of 300 yards or farther.
The Steyr IWS 2000
Steyr IWS 2000
The Steyr IWS 2000 is an Austrian semi-automatic anti-materiel rifle, produced by Steyr Mannlicher. IWS stands for Infantry Weapon System. It is actually a smoothbore weapon, like many modern tank guns, and not a true rifle but this can help accelerate projectiles and increase ballistic effectiveness...
is a closely related anti-material rifle. It shoots a 15.2mm sabot
Sabot
A sabot is a device used in a firearm or cannon to fire a projectile, such as a bullet, that is smaller than the bore diameter, or which must be held in a precise position. The term is also applied to a battery stub case, a device used similarly to make a small electrical battery usable in a...
ed, fin-stabilized, armor-piercing flechette made of tungsten carbide
Tungsten carbide
Tungsten carbide is an inorganic chemical compound containing equal parts of tungsten and carbon atoms. Colloquially, tungsten carbide is often simply called carbide. In its most basic form, it is a fine gray powder, but it can be pressed and formed into shapes for use in industrial machinery,...
or depleted uranium
Depleted uranium
Depleted uranium is uranium with a lower content of the fissile isotope U-235 than natural uranium . Uses of DU take advantage of its very high density of 19.1 g/cm3...
.
See also
- Rimfire ammunitionRimfire ammunitionA rimfire is a type of firearm cartridge. It is called a rimfire because instead of the firing pin of a gun striking the primer cap at the center of the base of the cartridge to ignite it , the pin strikes the base's rim....
- SabotSabotA sabot is a device used in a firearm or cannon to fire a projectile, such as a bullet, that is smaller than the bore diameter, or which must be held in a precise position. The term is also applied to a battery stub case, a device used similarly to make a small electrical battery usable in a...
- Caseless ammunitionCaseless ammunitionCaseless ammunition is a type of small arms ammunition that eliminates the cartridge case that typically holds the primer, propellant, and projectile together as a unit...
- Steyr IWS 2000Steyr IWS 2000The Steyr IWS 2000 is an Austrian semi-automatic anti-materiel rifle, produced by Steyr Mannlicher. IWS stands for Infantry Weapon System. It is actually a smoothbore weapon, like many modern tank guns, and not a true rifle but this can help accelerate projectiles and increase ballistic effectiveness...
- Steyr ACRSteyr ACRThe Steyr ACR was a prototype flechette-firing assault rifle built for the US Army's Advanced Combat Rifle program of 1989/90. Although the Steyr design proved effective, as did most of the weapons submitted, the entire ACR program ended with none of the entrants achieving performance 100% better...
- BullpupBullpupBullpups are firearm configurations in which the action is located behind the trigger group and alongside the shooter's face, so there is no wasted space for the buttstock as in conventional designs. This permits a shorter firearm length for the same barrel length for improved maneuverability, and...
- Steyr MannlicherSteyr MannlicherSteyr Mannlicher is a firearms manufacturer based in the city of Steyr, Austria. Originally a part of the Steyr-Daimler-Puch manufacturing conglomerate, it became independent when the conglomerate was broken in 1990.-History:...