Method of making polymeric subsonic ammunition

Patent metadata

Field	Value
Publication number	US-10190857-B2
Application number	US-201514751973-A
Country	US
Kind code	B2
Filing date	Jun 26, 2015
Priority date	Nov 10, 2010
Publication date	Jan 29, 2019
Grant date	Jan 29, 2019

Abstract

The present invention provides a method of making a subsonic ammunition 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 at least 10% 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

What is claimed is:

1. A method of making polymeric subsonic ammunition having a primer insert comprising the steps of:
providing a primer insert comprising 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 aperture positioned in the primer recess that extends through the bottom surface, and a flange that extends circumferentially about an outer edge of the top surface;
forming a substantially cylindrical polymeric middle body by overmolding a polymer composition over the substantially cylindrical coupling element and into the primer flash hole aperture to form a flash hole and extending from the primer insert to form a polymeric coupling end, thereby forming a propellant chamber;
forming a propellant insert adapted to fit in the propellant chamber;
positioning the propellant insert in the propellant chamber to reduce the propellant chamber by at least 10 percent;
forming a polymeric nose component comprising the steps of forming a polymeric nose coupling end opposite a bullet aperture, wherein the polymeric nose component is formed from a second polymer composition;
adhering the polymeric nose coupling end to the polymeric coupling end;
inserting a primer into the primer recess;
at least partially filling the propellant chamber with a propellant; and
frictionally fitting a projectile in the bullet aperture.

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

3. The method of claim 1 , wherein the internal volume is reduced by about 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25%.

4. The method of claim 1 , wherein the primer insert further comprises a flash hole groove formed around the primer flash hole aperture in the primer recess and the polymer extends into the flash hole groove.

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

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

7. The method of claim 1 , wherein the step of frictionally fitting the projectile in the bullet aperture comprises a mechanical interference, an adhesive, an ultrasonic welding, molding in place, bonding, welding, gluing, or hot crimping after molding of the projectile to the bullet aperture.

8. The method of claim 1 , wherein the polymer composition, the second polymer composition and the propellant insert independently comprises a polymer selected from the group consisting of polyurethane prepolymer, cellulose, fluoro-polymer, ethylene inter-polymer alloy elastomer, ethylene vinyl acetate, nylon, polyester elastomer, polyester sulfone, polyphenyl amide, polypropylene, polyvinylidene fluoride, thermoset polyurea elastomer, acrylics, homopolymers, acetates, copolymers, acrylonitrile-butadinen-styrene, thermoplastic fluoro polymers, inomers, polyamides, polyamide-imides, polyacrylates, polyatherketones, polyaryl-sulfones, polybenzimidazoles, 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 polyphenylsulfones 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.

9. The method of claim 1 , wherein the polymer composition, the second polymer composition and the propellant insert independently comprise a material selected from the group consisting of polyphenylsulfone, polycarbonate, and polyamide.

10. The method of claim 1 , wherein the polymer composition, the second polymer composition and the propellant insert independently comprise at least one additive selected from the group consisting of plasticizers, lubricants, molding agents, fillers, thermo-oxidative stabilizers, flame-retardants, coloring agents, compatibilizers, impact modifiers, release agents, reinforcing fibers and reinforcing agents.

11. The method of claim 1 , wherein the propellant insert has a substantially cylindrical shape.

12. The method of claim 1 , wherein the propellant insert has an irregular shape.

13. The method of claim 1 , wherein the propellant insert has one or more ribs extending into the propellant chamber.

14. The method of claim 1 , wherein the propellant insert has a radial cross-section selected from the group consisting of circular, ovoid, octagonal, hexagonal, triangular, star, ribbed, square and a combination thereof.

15. The method of claim 1 , wherein the-propellant insert is irregularly shaped or is longitudinally threaded.

16. The method of claim 1 , wherein the substantially cylindrical polymeric middle body, the polymeric nose component and the propellant insert independently comprise the same polymeric material or different polymeric materials.

17. The method of claim 1 , wherein the propellant chamber further comprises a second propellant insert in contact with the propellant insert disposed in the propellant chamber.

Assignees

• True Velocity Ip Holdings Llc

Inventors

• Burrow Lonnie

Classifications

• F42B5/307

  formed by assembling several elements · CPC title

• F42B33/02

  Filling cartridges, missiles, or fuzes; Inserting propellant or explosive charges {(F42B33/004 takes precedence)} · 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

• F42B33/0207

  Processes for loading or filling propulsive or explosive charges in containers · CPC title

• F42B33/001 Primary

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