Cartridges and cartridge cases adapted to be chambered in weapon systems are provided. In one example, a cartridge case includes a front shell having a case base end portion, a case body portion extending forward from the case base end portion towards a case mouth portion that is configured for holding a projectile. The case base end portion has a first interlocking feature. A reinforcing cap is disposed adjacent to the case base end portion on a side opposite the internal volume. The reinforcing cap has an annular extraction groove, a primer pocket, a flash hole for providing fluid communication between the primer pocket and the internal volume, and a second interlocking feature that engages the first interlocking feature to couple the reinforcing cap to the case base end portion.

Cartridges and cartridge cases adapted to be chambered in weapon systems are provided. In one example, a cartridge case includes a front shell having a case base end portion, a case body portion extending forward from the case base end portion towards a case mouth portion that is configured for holding a projectile. The case base end portion has a first interlocking feature. A reinforcing cap is disposed adjacent to the case base end portion on a side opposite the internal volume. The reinforcing cap has an annular extraction groove, a primer pocket, a flash hole for providing fluid communication between the primer pocket and the internal volume, and a second interlocking feature that engages the first interlocking feature to couple the reinforcing cap to the case base end portion.

The present invention provides a method of making a metal injection molded ammunition cartridge comprising the steps of: providing an ammunition cartridge mold comprising a bottom portion having a primer recess extending into the bottom portion adapted to receive a primer, a flash hole positioned in the primer recess through the bottom surface; side walls extending from the bottom portion to a nose end aperture, wherein a propellant chamber is formed between the nose end aperture and the bottom surface; injecting a metal composition into the ammunition cartridge mold to form a metal injection molded ammunition cartridge; and removing the metal injection molded ammunition cartridge from the ammunition cartridge mold.

The present invention provides a method of making a metal injection molded ammunition cartridge comprising the steps of: providing an ammunition cartridge mold comprising a bottom portion having a primer recess extending into the bottom portion adapted to receive a primer, a flash hole positioned in the primer recess through the bottom surface; side walls extending from the bottom portion to a nose end aperture, wherein a propellant chamber is formed between the nose end aperture and the bottom surface; injecting a metal composition into the ammunition cartridge mold to form a metal injection molded ammunition cartridge; and removing the metal injection molded ammunition cartridge from the ammunition cartridge mold.

The present invention provides a polymer nose for a polymeric ammunition cartridge having a generally cylindrical neck having a projectile aperture at a first end, a shoulder comprising a shoulder top connected to the generally cylindrical neck opposite a shoulder bottom, a side wall extending from the shoulder, a groove positioned around the side wall, a skirt connected circumferentially about the groove to extend away from the groove, wherein the groove and the skirt are adapted to mate to a polymer cartridge.

A system for firing reduced energy cartridges from a modern sporting rifle utilizes a bolt assembly weighing less than a conventional bolt assembly for such rifles and utilizes blow back for cycling the bolt assembly rather than gas operation. A bolt insert in a polymer bolt carrier of the bolt assembly has a projection that fits within a recess on the rear face of reduced energy cartridges. The reduced energy cartridges having a polymer casing, a rimfire power load for propellant, the power load recessed from the rear face of the casing. Tuning the bolt may comprise adjusting the weight of the bolt or the sliding resistance of the bolt assembly in the upper receiver. The bolt may be formed by metal injection molding with a polymer bolt carrier attached thereto.

The present invention provides polymeric ammunition cartridge having a generally cylindrical neck having a projectile aperture at a first end, an outer shoulder surface that extends from the generally cylindrical neck, an outer shoulder angle defined by the outer shoulder surface, an inner shoulder surface on the inside of the polymer nose opposite the outer shoulder surface, an inner shoulder angle defined by the outer shoulder surface, a skirt surface extending from the inner shoulder surface, a skirt angle defined by the skirt surface, and a nose junction that extends from the outer shoulder surface to the skirt surface, wherein the nose junction is adapted to mate to a polymer cartridge.

The present invention provides polymer ammunition having a generally cylindrical neck having a projectile aperture at a first end, a shoulder comprising a shoulder top connected to the generally cylindrical neck opposite a shoulder bottom, a nose junction positioned around the shoulder bottom, a skirt connected circumferentially about the nose junction to extend away from the shoulder bottom, wherein the nose junction and the skirt are adapted to mate to a base junction in a cartridge.

The present invention provides polymer ammunition, ammunition cartridge, ammunition case, and portions thereof having traditional and non-traditional cartridge shapes or profiles.

The present invention provides a A polymer nose for a polymeric ammunition cartridge having a generally cylindrical neck having a projectile aperture at a first end, an outer shoulder surface that extends from the generally cylindrical neck, an outer shoulder angle defined by the outer shoulder surface, an inner shoulder surface on the inside of the polymer nose opposite the outer shoulder surface, an inner shoulder angle defined by the outer shoulder surface, a skirt surface extending from the inner shoulder surface, a skirt angle defined by the skirt surface, and a nose junction that extends from the outer shoulder surface to the skirt surface, wherein the nose junction is adapted to mate to a polymer cartridge.