Method of making a polymeric subsonic ammunition cartridge

Patent metadata

Field	Value
Publication number	US-2017191811-A9
Application number	US-201514863567-A
Country	US
Kind code	A9
Filing date	Sep 24, 2015
Priority date	Nov 10, 2010
Publication date	Jul 6, 2017
Grant date	—

Abstract

The present invention provides a method of making a subsonic ammunition cartridge having a polymeric casing body having a generally cylindrical hollow polymer body having a body base at a first end thereof and a mouth at a second end to define a propellant chamber; a propellant insert positioned in the propellant chamber to reduce the internal volume of the propellant chamber, wherein the propellant chamber has an internal volume that is between 25 and 80% less than the open internal volume of a standard casing of equivalent caliber; and a primer insert positioned in the body base and in communication with the propellant chamber.

First claim

1 . A method of preparing a polymeric subsonic ammunition comprising the steps of:
providing a substantially cylindrical primer insert comprising a base having a top surface opposite a bottom surface, a substantially cylindrical coupling flange that extends from the top surface, a primer recess in the bottom surface, a flash hole aperture positioned in the primer recess extending through the bottom surface, a groove formed on the circumference of the bottom surface, and an extraction flange positioned about the circumference of the bottom surface; forming a polymeric middle body by molding at a first end a first polymer composition over the substantially cylindrical coupling flange into the flash hole aperture and molding and to a second end comprising a neck coupling region, wherein the first polymer composition extends from the neck coupling region to the primer flash hole aperture to form the polymeric middle body to form a propellant chamber; forming a polymeric bullet-end component from a second polymer composition, wherein the polymeric bullet-end component comprises a polymeric coupling region opposite a bullet aperture separated by a neck region; positioning a propellant chamber insert in the propellant chamber to reduce the internal volume of the propellant chamber, wherein the propellant chamber has an internal volume that is between 25 and 80% less than the open internal volume of a standard casing of equivalent caliber; and coupling the neck coupling region to the polymeric coupling region to form a propellant chamber from the bullet aperture to the primer flash hole aperture.

2 . The method of claim 1 , wherein the polymeric bullet-end component comprises a shoulder positioned between the substantially cylindrical polymeric coupling end and the bullet aperture.

3 . The method of claim 1 , wherein the propellant chamber insert reduces the internal volume by about 25.1, 25.2, 25.3, 25.4, 25.5, 25.6, 25.7, 25.8, 25.9, 26.0, 26.25, 26.5, 26.75, 27, 27.5, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80% or incremental variations thereof less than the open internal volume of a standard casing of equivalent caliber.

4 . (canceled)

5 . The method of claim 1 , wherein the substantially cylindrical primer insert further comprises a flash hole groove formed in the primer recess around the flash hole aperture and the first polymer composition extends to the flash hole groove to form a primer flash hole.

6 . The method of claim 1 , wherein the propellant chamber contains a propellant volume such that a projectile does not exceed a velocity of 1200 feet per second at sea level under standard atmospheric conditions when fired.

7 . The method of claim 1 , wherein the propellant chamber contains a propellant volume such that a projectile does not exceed the velocity of 1086 feet per second at standard atmospheric conditions when fired.

8 . The method of claim 1 , further comprising the step of securing a projectile to the bullet aperture by a mechanical interference, adhesive, ultrasonic welding, the combination of molding in place and adhesive, or hot crimping after molding.

9 . The method of claim 1 , wherein the first polymer composition comprises a polymers, copolymers of individual monomers selected from the group consisting of polybutylene terephthalates, 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 and copolymer mixtures thereof.

10 . The method of claim 1 , wherein the second polymer composition comprises a polymer, copolymer of individual monomers selected from the group consisting of 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.

11 . The method of claim 1 , wherein the propellant insertcomprises a polymer, copolymer of individual monomers selected from the group consisting of 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-

Assignees

• True Velocity Inc

Inventors

• Burrow Lonnie

Classifications

• 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

• F42B5/16

  characterised by composition or physical dimensions or form of propellant charge, {with or without projectile,} or powder (chemical composition C06B; {F42B5/24 takes precedence}) · CPC title

• F42C19/083

  characterised by the shape and configuration of the base element embedded in the cartridge bottom, e.g. the housing for the squib or percussion cap · CPC title

• F42B5/307

  formed by assembling several elements · CPC title

• F42B33/001 Primary

  Devices or processes for assembling ammunition, cartridges or cartridge elements from parts · CPC title