An ammunition article comprises a polymer cartridge case formed of a polymer composition comprising a thermoplastic polymer, preferably the polymer composition having a density of less than 1.35 determined in accordance with ASTM D792, the polymer cartridge case having a first end, an opposing second end, and a chamber disposed between the first end and the second end for receiving a propellant; a projectile attached to the first end of the polymer cartridge case; a metal base insert joined to the second end of the polymer cartridge case; and a primer carried by the metal base insert; wherein the metal base insert and the polymer cartridge case remain joined together as a single piece assembly upon loading, firing and removal from a chamber of a firearm for a polymer case temperature of −65° F. (−54° C.) to 165° F. (74° C.).

An ammunition article comprises a polymer cartridge case formed of a polymer composition comprising a thermoplastic polymer, preferably the polymer composition having a density of less than 1.35 determined in accordance with ASTM D792, the polymer cartridge case having a first end, an opposing second end, and a chamber disposed between the first end and the second end for receiving a propellant; a projectile attached to the first end of the polymer cartridge case; a metal base insert joined to the second end of the polymer cartridge case; and a primer carried by the metal base insert; wherein the metal base insert and the polymer cartridge case remain joined together as a single piece assembly upon loading, firing and removal from a chamber of a firearm for a polymer case temperature of −65° F. (−54° C.) to 165° F. (74° C.).

A firearm system includes a bolt carrier with an internal cavity, a piston disposed within the internal cavity, a forward configuration where the piston is in a forwardmost position relative to the bolt carrier, and an aft configuration where the piston is in a rearmost position relative to the bolt carrier. The piston slides forward and aft relative to the bolt carrier. In the forward configuration, the entire piston remains disposed within the bolt carrier.

A firearm system includes a bolt carrier with an internal cavity, a piston disposed within the internal cavity, a forward configuration where the piston is in a forwardmost position relative to the bolt carrier, and an aft configuration where the piston is in a rearmost position relative to the bolt carrier. The piston slides forward and aft relative to the bolt carrier. In the forward configuration, the entire piston remains disposed within the bolt carrier.

One embodiment of the present invention provides a polymeric ammunition cartridge and methods of making and using the same. The cartridge includes a substantially cylindrical insert connected to a substantially cylindrical polymeric middle body. The substantially cylindrical insert includes a top surface opposite a bottom surface and a substantially cylindrical coupling element that extends from the bottom surface, a primer recess in the top surface that extends toward the bottom surface, a primer flash hole positioned in the primer recess to extend through the bottom surface, and a flange that extends circumferentially about an outer edge of the top surface. The substantially cylindrical polymeric middle body includes a substantially cylindrical polymeric bullet-end and a substantially cylindrical polymeric coupling end connected by a powder chamber, wherein the substantially cylindrical polymeric coupling end extends over the substantially cylindrical coupling element and covers a circumferential surface of the primer flash hole.

One embodiment of the present invention provides a polymeric ammunition cartridge and methods of making and using the same. The cartridge includes a substantially cylindrical insert connected to a substantially cylindrical polymeric middle body. The substantially cylindrical insert includes a top surface opposite a bottom surface and a substantially cylindrical coupling element that extends from the bottom surface, a primer recess in the top surface that extends toward the bottom surface, a primer flash hole positioned in the primer recess to extend through the bottom surface, and a flange that extends circumferentially about an outer edge of the top surface. The substantially cylindrical polymeric middle body includes a substantially cylindrical polymeric bullet-end and a substantially cylindrical polymeric coupling end connected by a powder chamber, wherein the substantially cylindrical polymeric coupling end extends over the substantially cylindrical coupling element and covers a circumferential surface of the primer flash hole.

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.

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.

The present invention provides three piece primer insert for use in polymer ammunition comprising: an upper primer insert portion comprising an upper primer insert bottom portion, a substantially cylindrical coupling element extending away from the upper primer insert bottom portion; and an upper flash aperture that extends through the upper primer insert bottom portion, a lower primer insert portion in contact with the upper primer insert portion, wherein the lower primer insert portion comprises a lower primer insert top portion positioned adjacent to the upper primer insert bottom portion at a connection joint, a lower flash aperture positioned in the lower primer insert top portion and aligned with the upper flash aperture, and a primer recess that extends away from the lower primer insert top portion to an extraction flange and in communication with the lower flash aperture; and a connecting portion that secures the upper primer insert portion and the lower primer insert portion wherein the connecting portion comprises a connecting member positioned in the upper flash aperture and the lower flash aperture, an upper tab connected to the connecting member to extend away from the upper flash aperture into the upper primer insert portion, a lower tab connected to the connecting member to extend away from the lower flash aperture into the primer recess, and a flash hole that extends from the upper tab to the lower tab to connect the upper primer insert bottom portion to the primer recess.

The present invention provides three piece primer insert for use in polymer ammunition comprising: an upper primer insert portion comprising an upper primer insert bottom portion, a substantially cylindrical coupling element extending away from the upper primer insert bottom portion; and an upper flash aperture that extends through the upper primer insert bottom portion, a lower primer insert portion in contact with the upper primer insert portion, wherein the lower primer insert portion comprises a lower primer insert top portion positioned adjacent to the upper primer insert bottom portion at a connection joint, a lower flash aperture positioned in the lower primer insert top portion and aligned with the upper flash aperture, and a primer recess that extends away from the lower primer insert top portion to an extraction flange and in communication with the lower flash aperture; and a connecting portion that secures the upper primer insert portion and the lower primer insert portion wherein the connecting portion comprises a connecting member positioned in the upper flash aperture and the lower flash aperture, an upper tab connected to the connecting member to extend away from the upper flash aperture into the upper primer insert portion, a lower tab connected to the connecting member to extend away from the lower flash aperture into the primer recess, and a flash hole that extends from the upper tab to the lower tab to connect the upper primer insert bottom portion to the primer recess.