The present invention provides an injection molded primer insert for polymer ammunition comprising: a top surface opposite a bottom surface; a primer flash hole aperture positioned in the top surface extending through to the bottom surface; a substantially cylindrical coupling element extending away from the bottom surface forming an interior surface inside the substantially cylindrical coupling element and an exterior surface; a primer recess in the top surface that extends toward the bottom surface, a primer flash aperture 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, wherein the flange is adapted to receive a polymer overmolding.

One embodiment of the present invention provides a stamped metal primer insert for a polymeric ammunition cartridge comprising: a top surface having a stamped flange that extends circumferentially about an outer edge of the top surface; a stamped coupling element that extends from the flange to a coupling tip; a stamped inner coupling element from the coupling tip to a bottom surface, wherein the bottom surface is opposite the top surface; a stamped primer recess in the top surface that extends toward the bottom surface; a primer flash aperture in the primer recess through the bottom surface; and a groove stamped in the primer recess around the primer flash aperture adapted to receive a polymer overmolding.

The present invention provides ammunition cartridge having a two piece primer insert with a flange, a polymeric middle body extending from the primer insert to a cylindrical middle body coupling region, and a polymeric projectile end having a projectile aperture mated to the polymeric middle body.

The present invention provides ammunition cartridge having a two piece primer insert with a flange, a polymeric middle body extending from the primer insert to a cylindrical middle body coupling region, and a polymeric projectile end having a projectile aperture mated to the polymeric middle body.

The present invention provides a single piece polymer ammunition cartridge and polymer ammunition and methods of forming a single piece polymer ammunition cartridge and polymer ammunition.

A method of manufacturing a casing for an ammunition cartridge includes injection molding a polymer forming the casing using an injection mold. The casing is cylindrically shaped along a longitudinal axis extending from a base to a distal end with a blind hole formed therein. The blind hole has a primer retention feature disposed at the base and leads into a flash hole. An insulator and/or reflector is placed around at least a portion of the casing separating the base from the neck. A heater directly heats the neck of the casing while not directly heating the base. A stretch rod is inserted into the blind hole stretching the neck. The casing is inserted into a blow mold and pressurized causing the neck of the casing to be blow molded. At least a portion of the distal end of the casing is removed.

A method of manufacturing a casing for an ammunition cartridge includes injection molding a polymer forming the casing using an injection mold. The casing is cylindrically shaped along a longitudinal axis extending from a base to a distal end with a blind hole formed therein. The blind hole has a primer retention feature disposed at the base and leads into a flash hole. An insulator and/or reflector is placed around at least a portion of the casing separating the base from the neck. A heater directly heats the neck of the casing while not directly heating the base. A stretch rod is inserted into the blind hole stretching the neck. The casing is inserted into a blow mold and pressurized causing the neck of the casing to be blow molded. At least a portion of the distal end of the casing is removed.

The present invention provides a multi piece primer insert for ammunition comprising: an upper primer insert portion connected to a lower primer insert portion, wherein the upper primer insert portion comprises an upper primer bottom surface and an upper primer top surface opposite the upper primer bottom surface, an upper primer aperture through the upper primer bottom surface, a substantially cylindrical coupling element extending away from the upper primer bottom surface, wherein the lower primer insert comprises: a lower primer top surface opposite a lower primer bottom surface, a primer recess in the lower primer top surface that extends toward the lower primer bottom surface and adapted to fit a primer, a lower flash hole aperture through the lower primer bottom surface extending to the primer recess; and a flash hole groove in the top surface of the upper primer insert portion, the flash hole groove extends circumferentially about the upper primer aperture and the flash hole groove is larger than the upper primer aperture, and wherein the flash hole groove is between the upper primer aperture and the lower flash hole aperture.

The present invention provides a multi piece primer insert for ammunition comprising: an upper primer insert portion connected to a lower primer insert portion, wherein the upper primer insert portion comprises an upper primer bottom surface and an upper primer top surface opposite the upper primer bottom surface, an upper primer aperture through the upper primer bottom surface, a substantially cylindrical coupling element extending away from the upper primer bottom surface, wherein the lower primer insert comprises: a lower primer top surface opposite a lower primer bottom surface, a primer recess in the lower primer top surface that extends toward the lower primer bottom surface and adapted to fit a primer, a lower flash hole aperture through the lower primer bottom surface extending to the primer recess; and a flash hole groove in the top surface of the upper primer insert portion, the flash hole groove extends circumferentially about the upper primer aperture and the flash hole groove is larger than the upper primer aperture, and wherein the flash hole groove is between the upper primer aperture and the lower flash hole aperture.

The present invention provides a multi piece primer insert for ammunition comprising an upper primer insert portion connected to a lower primer insert portion, wherein the upper primer insert portion comprises an upper primer bottom surface; an upper primer aperture through the upper primer bottom surface, and a substantially cylindrical coupling element extending away from the upper primer bottom surface, wherein the lower primer insert portion comprises: a lower primer bottom surface opposite a lower primer top surface, a primer recess in the lower primer top surface that extends toward the lower primer bottom surface and adapted to fit a primer, a lower flash hole aperture through the lower primer bottom surface, wherein the lower flash hole aperture is about the same diameter as the upper primer aperture; a middle flash hole aperture positioned between the upper primer aperture and the lower flash hole aperture, wherein the middle flash hole aperture has a diameter greater than the lower flash hole aperture at the junction of the upper primer insert portion the lower primer insert portion.