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 polymer ammunition cartridge having a primer insert having: a top surface; a bottom surface opposite the top surface; a coupling element that extends from the bottom surface, wherein the coupling element comprises an interior surface and an exterior surface, wherein the interior surface comprises: a transition region that transitions from the bottom surface to a second segment wherein the transition region has a radius of from 0.02 to 0.2; a first segment extending from the second segment and terminates at a tip, wherein the first segment has a first segment distance from 0.02 to 0.18 inches and the second segment has a second segment distance from 0.02 to 0.18 inches, wherein the second segment has a second segment angle from +3 to −3 degrees relative to the first segment angle and the first segment has a first segment angle from +6 to −6 degrees from perpendicular to the top surface; a primer recess in the top surface that extends toward the bottom surface; a primer flash aperture positioned in the primer recess through the bottom surface; and a flash aperture groove in the primer recess and positioned around the primer flash aperture and adapted to receive a polymer overmolding through the primer flash aperture.

The present invention provides a method of forming a chamber in a firearm wherein the chamber is adapted to fit a polymer ammunition cartridge comprising the steps of: providing a barrel blank; providing a reamer having the dimensions of the desired polymer ammunition cartridge, wherein the reamer comprising a reamer profile corresponding to an ammunition cartridge having a reduced neck height comprising: a shortened neck having a projectile aperture, wherein the shortened neck is reduced by 25-100% of the neck height of a standard cartridge neck; a shoulder extending from the shortened neck to a cartridge side wall; and wherein the cartridge side wall extends from the shoulder to the base to form an interior propellant chamber; wherein the base comprises an extraction ring, a primer recess positioned in the base in communication with the propellant chamber through a flash hole that extends from the primer recess into the propellant chamber; contacting the reamer with the barrel blank to form a reamed barrel having a chamber having the corresponding profile that mates to the reamer profile; removing the reamer from the reamed barrel.

The present invention provides a method of forming a chamber in a firearm wherein the chamber is adapted to fit a polymer ammunition cartridge comprising the steps of: providing a barrel blank; providing a reamer having the dimensions of the desired polymer ammunition cartridge, wherein the reamer comprising a reamer profile corresponding to an ammunition cartridge having a reduced neck height comprising: a shortened neck having a projectile aperture, wherein the shortened neck is reduced by 25-100% of the neck height of a standard cartridge neck; a shoulder extending from the shortened neck to a cartridge side wall; and wherein the cartridge side wall extends from the shoulder to the base to form an interior propellant chamber; wherein the base comprises an extraction ring, a primer recess positioned in the base in communication with the propellant chamber through a flash hole that extends from the primer recess into the propellant chamber; contacting the reamer with the barrel blank to form a reamed barrel having a chamber having the corresponding profile that mates to the reamer profile; removing the reamer from the reamed barrel.

The present invention provides a polymeric ammunition cartridge comprising: a three piece primer insert; a substantially cylindrical polymeric middle body extending about the three piece primer insert, wherein the substantially cylindrical polymeric middle body comprises: a substantially cylindrical polymeric bullet-end coupling element at a first end of the substantially cylindrical polymeric middle body opposite 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 an circumferential surface of the primer flash hole aperture; and a substantially cylindrical polymeric bullet-end upper portion comprising a bullet-end coupling element connected to the substantially cylindrical polymeric bullet-end coupling element opposite a projectile aperture adapted to engage a bullet.

The present invention provides a polymeric ammunition cartridge comprising: a three piece primer insert; a substantially cylindrical polymeric middle body extending about the three piece primer insert, wherein the substantially cylindrical polymeric middle body comprises: a substantially cylindrical polymeric bullet-end coupling element at a first end of the substantially cylindrical polymeric middle body opposite 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 an circumferential surface of the primer flash hole aperture; and a substantially cylindrical polymeric bullet-end upper portion comprising a bullet-end coupling element connected to the substantially cylindrical polymeric bullet-end coupling element opposite a projectile aperture adapted to engage a bullet.

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

The present invention provides an ammunition cartridge having a primer insert having a top surface opposite a bottom surface and a extraction flange that extends circumferentially about an outer edge of the top surface; a coupling element that extends from the bottom surface, wherein the substantially cylindrical coupling element is adapted to receive a polymer overmolding; a primer recess in the top surface that extends toward the bottom surface, wherein the primer recess comprises a recess bottom and a circular recess side wall; a primer flash aperture through the recess bottom that extends through the bottom surface, wherein the primer flash aperture is adapted to receive a polymer overmolding to form a flash hole; and a groove in the primer recess positioned around the primer flash aperture adapted to receive a polymer overmolding, wherein the groove extends at least partially over the bottom surface and the circular recess side wall and the groove is adapted to receive polymer through the primer flash aperture and over the bottom surface and the circular recess side wall.

The present invention provides a polymer ammunition cartridge having a primer insert having: a top surface; a bottom surface opposite the top surface; a coupling element that extends from the bottom surface, wherein the coupling element comprises an interior surface and an exterior surface, wherein the interior surface comprises: a transition region that transitions from the bottom surface to a second segment wherein the transition region has a radius of from 0.02 to 0.2; a first segment extending from the second segment and terminates at a tip, wherein the first segment has a first segment distance from 0.02 to 0.18 inches and the second segment has a second segment distance from 0.02 to 0.18 inches, wherein the second segment has a second segment angle from +3 to −3 degrees relative to the first segment angle and the first segment has a first segment angle from +6 to −6 degrees from perpendicular to the top surface; a primer recess in the top surface that extends toward the bottom surface; a primer flash aperture positioned in the primer recess through the bottom surface; and a flash aperture groove in the primer recess and positioned around the primer flash aperture and adapted to receive a polymer overmolding through the primer flash aperture.