Method of Stamping a Primer Insert for Use in Polymer Ammunition

Abstract

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

What is claimed is: 
     
         1 . A method of stamping a metal primer insert for a polymeric ammunition cartridge comprising the steps of:
 providing an insert blank for stamping;   stamping the insert blank to form a top surface having a flange that extends circumferentially about an outer edge of the top surface;   stamping the insert blank to form a substantially cylindrical coupling element that extends from the flange to a coupling tip;   stamping the insert blank to form an inner coupling element from the coupling tip to a bottom surface, wherein the bottom surface is opposite the top surface;   stamping the insert blank to form a primer recess in the top surface that extends toward the bottom surface;   stamping the insert blank to form a primer flash aperture in the primer recess through the bottom surface; and   stamping the insert blank to form a groove in the primer recess around the primer flash aperture adapted to receive a polymer overmolding.   
     
     
         2 . The method of  claim 1 , wherein the stamping comprises one or more progressive dies. 
     
     
         3 . The method of  claim 1 , wherein the insert blank is a sheet. 
     
     
         4 . The method of  claim 1 , wherein the insert blank is a coil. 
     
     
         5 . The method of  claim 1 , wherein the insert blank is a cylinder. 
     
     
         6 . The method of  claim 1 , further comprising the step of texturing the insert blank. 
     
     
         7 . The method of  claim 1 , wherein the primer flash aperture is larger than a flash hole in a standard primer insert of the same caliber. 
     
     
         8 . The method of  claim 1 , wherein the primer flash aperture is larger than a flash hole in a standard primer insert of the same caliber to allow polymer overmolding into the primer flash aperture. 
     
     
         9 . The method of  claim 1 , wherein the metal primer insert is a 5.56 mm, 7.62 mm, 0.223, 308, 338, 3030, 3006, and .50 caliber primer insert. 
     
     
         10 . The method of  claim 1 , wherein the metal primer insert is a 380 caliber, 38 caliber, 9 mm, 10 mm, 20 mm, 25 mm, 30 mm, 40 mm, 45 caliber and the like. 
     
     
         11 . The method of  claim 1 , wherein the insert blank is a metal, an alloy, or a ceramic alloy. 
     
     
         12 . The method of  claim 1 , wherein the insert blank is stainless steel or brass. 
     
     
         13 . The method of  claim 1 , wherein the insert blank is a 102, 174, 201, 202, 300, 302, 303, 304, 308, 309, 316, 316L, 316Ti, 321, 405, 408, 409, 410, 415, 416, 416R, 420, 430, 439, 440, 446 or 601-665 grade stainless steel. 
     
     
         14 . The method of  claim 1 , wherein the insert blank is a Ti6A14V.