Method of Making a Primer Insert for Use in Polymer Ammunition

Patent metadata

Field	Value
Publication number	US-2018224253-A1
Application number	US-201815911544-A
Country	US
Kind code	A1
Filing date	Mar 5, 2018
Priority date	Nov 10, 2010
Publication date	Aug 9, 2018
Grant date	—

Abstract

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.

First claim

1 - 23 . (canceled)

24 . A method of making a metal primer insert for a polymeric ammunition cartridge comprising the steps of:
providing an insert blank for milling; milling a top surface on the insert blank; milling a flange that extends circumferentially about an outer edge of the top surface; milling a outer channel adjacent to the flange that extends circumferentially about the insert blank, wherein the outer channel is adapted to receive a polymer overmolding; milling a substantially cylindrical coupling element that extends from the outer channel to a coupling tip; milling an inner coupling element from the coupling tip to a bottom surface, wherein the bottom surface is opposite the top surface, wherein the substantially cylindrical coupling element is adapted to receive a polymer overmolding; milling a primer recess in the top surface that extends toward the bottom surface; milling a primer flash aperture in the primer recess through the bottom surface; and milling a groove in the primer recess around the primer flash aperture adapted to receive a polymer overmolding.

25 . The method of claim 24 , wherein the primer flash aperture is larger than a flash hole in a standard primer insert of the same caliber.

26 . The method of claim 24 , 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.

27 . The method of claim 24 , wherein the metal primer insert is a 5.56 mm, 7.62 mm, .223, 308, 338, 3030, 3006, and 0.50 caliber primer insert.

28 . The method of claim 24 , 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.

29 . The method of claim 24 , wherein the insert blank is a metal, an alloy, or a ceramic alloy.

30 . The method of claim 24 , wherein the insert blank is stainless steel or brass.

31 . The method of claim 24 , 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 steel

32 . The method of claim 24 , wherein the insert blank is a Ti6Al4V.

Assignees

• True Velocity Inc

Inventors

• Burrow Lonnie

Classifications

• B22F2998/10

  Processes characterised by the sequence of their steps · CPC title

• F42B5/307 Primary

  formed by assembling several elements · CPC title

• F42B5/02

  Cartridges, i.e. cases with charge and missile · CPC title

• F42B5/025

  characterised by the dimension of the case or the missile · CPC title

• F42C19/0823

  Primers or igniters for the initiation or the propellant charge in a cartridged ammunition (primers for caseless ammunition F42C19/085) · CPC title