Abstract: A subsonic ammunition cartridge casing having an engineered internal volume designed to allow for the introduction of precisely the amount of propellant necessary at precisely the desired location to reproducibly produce the desired projectile velocity and internal pressure is provided. The subsonic shell casing has an engineered internal propellant cavity built into the internal body of the casing itself that does not necessarily depend on the introduction of a separate volume reducing device such as tubing, filler, foam filler and the like. This ensures the integrity of the case, does not result in anything being expelled through the muzzle of the weapon other than the projectile, does not have any burning or combusting components, allows for very precise control of the internal volume and thus chamber pressure, and is economical to produce.

Abstract: An ammunition cartridge casing having a geometry designed to allow for the use of polymeric materials in forming the walls of the cartridge casing of an ammunition article, and methods of reusing such cartridges are provided. More specifically, the ammunition cartridge has a specified ratio between the wall-thicknesses of select portions of an ammunition article's cartridge casing such that polymeric materials may be used in the construction of the ammunition article cartridge casings.

Abstract: An ammunition cartridge casing having a geometry designed to allow for the use of polymeric materials in forming the walls of the cartridge casing of an ammunition article, and methods of reusing such cartridges are provided. More specifically, the ammunition cartridge has a specified ratio between the wall-thicknesses of select portions of an ammunition article's cartridge casing such that polymeric materials may be used in the construction of the ammunition article cartridge casings.

Abstract: A subsonic ammunition cartridge casing having an engineered internal volume designed to allow for the introduction of precisely the amount of propellant necessary at precisely the desired location to reproducibly produce the desired projectile velocity and internal pressure is provided. The subsonic shell casing has an engineered internal propellant cavity built into the internal body of the casing itself that does not necessarily depend on the introduction of a separate volume reducing device such as tubing, filler, foam filler and the like. This ensures the integrity of the case, does not result in anything being expelled through the muzzle of the weapon other than the projectile, does not have any burning or combusting components, allows for very precise control of the internal volume and thus chamber pressure, and is economical to produce.