Polymer ammunition cartridge having a metal injection molded primer insert

Patent metadata

Field	Value
Publication number	US-2017167835-A9
Application number	US-201514748880-A
Country	US
Kind code	A9
Filing date	Jun 24, 2015
Priority date	Nov 10, 2010
Publication date	Jun 15, 2017
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

What is claimed is:

1 . An ammunition cartridge having a molded primer insert comprising:
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; a substantially cylindrical polymeric middle body extending from the substantially cylindrical primer insert to a cylindrical middle body coupling region molded from a first polymer, wherein the first polymer is molded over the flange, the inner circumferential surface and the outer surface and extends to the cylindrical middle body coupling region; a substantially cylindrical polymeric projectile end mated to the substantially cylindrical polymeric middle body, wherein the substantially cylindrical polymeric projectile end comprises a second polymer composition forming a projectile end coupling region that extends to a shoulder region that reduces to a neck region having a projectile aperture wherein the projectile end coupling region couples to the middle body coupling region; and a propellant chamber defined between the primer flash aperture and the projectile aperture.

2 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert comprises a metal, an alloy, or a ceramic alloy.

3 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert comprises stainless steel or brass.

4 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert comprises 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.

5 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert comprises 2-16% Ni; 10-20% Cr; 0-5% Mo; 0-0.6% C; 0-6.0% Cu; 0-0.5% Nb+Ta; 0-4.0% Mn; 0-2.0% Si and the balance Fe.

6 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert comprises 2-6% Ni; 13.5-19.5% Cr; 0-0.10% C; 1-7.0% Cu; 0.05-0.65% Nb+Ta; 0-3.0% Mn; 0-3.0% Si and the balance Fe.

7 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert comprises 3-5% Ni; 15.5-17.5% Cr; 0-0.07% C; 3-5.0% Cu; 0.15-0.45% Nb+Ta; 0-1.0% Mn; 0-1.0% Si and the balance Fe.

8 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert comprises 10-14% Ni; 16-18% Cr; 2-3% Mo; 0-0.03% C; 0-2% Mn; 0-1% Si and the balance Fe.

9 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert comprises 12-14% Cr; 0.15-0.4% C; 0-1% Mn; 0-1% Si and the balance Fe.

10 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert comprises 16-18% Cr; 0-0.05% C; 0-1% Mn; 0-1% Si and the balance Fe.

11 . The ammunition cartridge of claim 1 , wherein the powdered metal comprises 3-12% aluminum, 2-8% vanadium, 0.1-0.75% iron, 0.1-0.5% oxygen, and the remainder titanium.

12 . The ammunition cartridge of claim 1 , wherein the powdered metal comprises about 6% aluminum, about 4% vanadium, about 0.25% iron, about 0.2% oxygen, and the remainder titanium.

13 . The ammunition cartridge of claim 1 , further comprising a primer flash aperture groove positioned in the primer recess around the primer flash aperture and the first polymer composition extends into the primer flash aperture to form a flash hole.

14 . The ammunition cartridge of claim 1 , wherein the first polymer composition is the same as the second polymer composition.

15 . The ammunition cartridge of claim 1 , wherein the first polymer composition, the second polymer composition or both comprise a nylon polymer.

16 . The ammunition cartridge of claim 1 , wherein the first polymer composition, the second polymer composition or both comprise a fiber-reinforced polymeric composite.

17 . The ammunition cartridge of claim 1 , wherein the first polymer composition, the second polymer composition or both comprise between about 10 and about 70 wt % glass fiber fillers, mineral fillers, or mixtures thereof.

18 . The ammunition cartridge of claim 1 , wherein the bullet aperture comprises one or more cannelures formed on an inner circumferential surface of the bullet aperture.

19 . The ammunition cartridge of claim 1 , wherein the substantially cylindrical coupling region and the polymeric bullet-end coupling are welded or bonded together.

20 . The ammunition cartridge of claim 1 , wherein the first polymer composition, the second polymer composition or both comprise polyurethane prepolymer, cellulose, fluoro-polymer, ethylene inter-polymer alloy elastomer, ethylene vinyl acetate, nylon, polyether imide, polyester elastomer, polyester sulfone, polyphenyl amide, polypropylene, polyvinylidene fluoride or thermoset polyurea elastomer, acrylics, homopolymers, acetates, copolymers, acrylonitrile-butadiene-styrene, thermoplastic fluoro polymers, inomers, polyamides, polyamide-imides, polyacrylates, polyatherketones, polyaryl-sulfones, polybenzimidazoles, polycarbonates, polybutylene, terephthalates, polyether imides, polyether sulfones, thermoplastic polyimides, thermoplastic polyurethanes, polyphenylene sulfides, polyethylene, polypropylene, polysulfones, polyvinylchlorides, styrene acrylonitriles, polystyrenes, polyphenylene, ether blends, styrene maleic anhydrides, polycarbonates, allyls, aminos, cyanates, epoxies, phenolics, unsaturated polyesters, bismaleimides, polyurethanes, silicones, vinylesters, urethane hybrids, polyphenylsulfones, copolymers of polyphenylsulfones with polyethersulfones or polysulfones, copolymers of poly-phenylsulfones with siloxanes, blends of polyphenylsulfones with polysiloxanes, poly(etherimide-siloxane) copolymers, blends of polyetherimides and polysiloxanes, and blends of polyetherimides and poly(etherimide-siloxane) copolymers.

21 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert is about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 percent smaller than a precured injection molded primer insert.

22 . The ammunition cartridge of claim 1 , wherein the injection molded primer insert further comprises a flash hole groove that extends circumferentially about the primer flash aperture on the top surface in the primer recess.

23 . The ammunition cartridge of claim 1 , wherein the bottom surface comprises a circumferential groove.

24 . The ammunition cartridge of claim 1 , wherein the flange comprises 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 notches positioned circumferential.

25 . The ammunition cartridge of claim 1 , wherein the flange comprises 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 scallops positioned circumferential.

Assignees

• True Velocity Inc

Inventors

• Burrow Lonnie

Classifications

• C22C38/44

  with molybdenum or tungsten · CPC title

• F42C19/0807

  characterised by the particular configuration of the transmission channels from the priming energy source to the charge to be ignited, e.g. multiple channels, nozzles, diaphragms or filters · CPC title

• B22F2998/10

  Processes characterised by the sequence of their steps · CPC title

• C22C38/02

  containing silicon · CPC title

• C22C38/58

  with more than 1.5% by weight of manganese · CPC title