| 主权项 |
1. A method of making polymer ammunition having a two piece primer insert comprising by the steps of:
providing a two piece primer insert comprising: an upper primer insert portion comprising an 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, and an interior surface inside the substantially cylindrical coupling element; a lower primer insert portion comprising 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 the primer recess adapted to fit a primer, a lower primer aperture through the lower primer bottom surface, and a flange that extends circumferentially about an outer edge of the lower primer top bottom surface, wherein the flange is adapted to receive a polymer overmolding; and an insert joint that links the upper primer bottom surface and the lower primer bottom surface to align the lower primer aperture with the upper primer aperture and forming the two piece primer insert; providing a primer flash hole aperture extending through the lower primer aperture and the upper primer aperture; providing a first polymer composition for molding the polymer ammunition cartridge; molding from the first polymer composition a substantially cylindrical polymeric middle body having the two piece primer insert at a first end and a substantially cylindrical polymeric coupling region at a second end, wherein the first polymer composition extends over an outer surface of the two piece primer insert over the flange and the first polymer composition extends over the interior surface of the substantially cylindrical coupling element and into the primer flash hole aperture, wherein the first polymer composition extends from the substantially cylindrical polymeric coupling region into the primer flash hole aperture; forming a substantially cylindrical polymeric bullet-end component from a second polymer composition comprising a bullet aperture opposite a polymeric bullet-end coupling that mates to the substantially cylindrical coupling region; coupling the substantially cylindrical coupling region to the polymeric bullet-end coupling to form a propellant chamber that extends from the primer flash hole aperture to the bullet aperture; inserting a primer into the primer recess, wherein the primer is in operable communication with the propellant chamber through the primer flash hole aperture; at least partially filling the propellant chamber with a propellant; and frictionally fitting a projectile in the bullet aperture, wherein the propellant chamber is enclosed at one end by the primer and the projectile at the other end. |
