Lightweight Polymer Cased Ammunition

Abstract

One embodiment of the present invention provides a polymeric ammunition cartridge, polymeric ammunition and methods of making the same.

What is claimed is: 
     
         1 . A polymer ammunition cartridge comprising:
 a polymer cartridge  12  comprising
 a projectile aperture  22  adapted to receive a projectile, 
 a cartridge neck  24  extending from the projectile aperture  22  to a cartridge shoulder  26 , and 
 a cartridge sidewall  28  extending from the cartridge shoulder  26 , to an cap coupling segment  30 ; 
   a retaining cap  42  comprising
 a substantially cylindrical retaining side wall  44  extending to a retaining cap bottom surface  48 , 
 a retaining cap cavity  50  positioned about the substantially cylindrical retaining side wall  44 , and 
 a retaining cap aperture  52  extending through the retaining cap bottom surface  48 , wherein the substantially cylindrical retaining side wall  44  is positioned within the cap coupling segment  30 ; 
   a substantially cylindrical cartridge cap  18  comprising
 a substantially cylindrical cartridge coupling element  32  that extends to a substantially cylindrical cap bottom surface  34 , 
 a substantially cylindrical primer end  36  positioned opposite the substantially cylindrical cap bottom surface  34 , 
 a primer recess  38  in the substantially cylindrical primer end  36  that extends toward the substantially cylindrical cap bottom surface  34 , 
 a primer flash hole  40  positioned in the primer recess  38  to extend through the substantially cylindrical cap bottom surface  34 , and 
 a flange  39  that extends circumferentially about an outer edge of the substantially cylindrical primer end  36 , 
 wherein the cap coupling segment  30  is positioned within the substantially cylindrical cartridge coupling element  32  such that the cap coupling segment  30  is compressed between the substantially cylindrical retaining side wall  44  and the substantially cylindrical cartridge coupling element  32 ; 
 at least a portion of the cartridge coupling element  32  is crimped into the retaining cap cavity  50 ; and the primer flash hole  40  and the retaining cap aperture  52  are at least partially aligned. 
   
     
     
         2 . The polymeric ammunition cartridge of  claim 1 , wherein the polymer cartridge  12  comprise a polymers selected from the group consisting of nylon, including nylon 6, nylon copolymers and terpolymers, nylon 6,10 and nylon 6,12, long-chain nylon chemistry alternatives to nylon 11 and nylon 12, as well as a broad variety of compounded nylon materials, 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-butadinen-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, polyphenylsulfone, 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 crosslinked polymers. 
     
     
         3 . The polymeric ammunition cartridge of  claim 1 , wherein the polymer cartridge  12  comprises a polyethylene, poly (phenylsulfone), a nylon or both. 
     
     
         4 . The polymeric ammunition cartridge of  claim 2 , wherein at least a portion of the polymer further comprises between about 0.1 and about 70 wt % carbon fibers fillers, glass fiber fillers, mineral fillers, or mixtures thereof. 
     
     
         5 . The polymeric ammunition cartridge of  claim 1 , wherein at least a portion of the cap coupling segment  30  is compressed into the retaining cap cavity  50 . 
     
     
         6 . The polymeric ammunition cartridge of  claim 1 , wherein at least a portion of the cap bottom surface  34  is secured to the retaining cap bottom surface  48 . 
     
     
         7 . The polymeric ammunition cartridge of  claim 1 , wherein at least a portion of the cap bottom surface  34  is connected with an adhesive to the retaining cap bottom surface  48 . 
     
     
         8 . The polymeric ammunition cartridge of  claim 1 , further comprising a primer disposed in the primer recess  38 , a propellent deposited in the polymer cartridge  12  and a projectile positioned in the projectile aperture  22 . 
     
     
         9 . A method of forming an ammunition cartridge from a polymer comprising the steps of:
 providing a polymer;   forming a projectile aperture  22  adapted to receive a projectile in the polymer;   extending the polymer from the projectile aperture  22  to form a cartridge neck  24 ;   extending the polymer from the cartridge neck  24  to form a cartridge shoulder  26 ; and   extending the polymer from the cartridge shoulder  26  to an cap coupling segment  30  to form a cartridge sidewall  28 .   
     
     
         10 . The method of  claim 9 , further comprising the step of
 providing a retaining cap  42  comprising a substantially cylindrical retaining side wall  44  extending to a retaining cap bottom surface  48 , a retaining cap cavity  50  positioned about the substantially cylindrical retaining side wall  44 , and a retaining cap aperture  52  extending through the retaining cap bottom surface  48 ;   positioning the substantially cylindrical retaining side wall  44  within the cap coupling segment  30 ;   providing a substantially cylindrical cartridge cap  18  comprising a substantially cylindrical cartridge coupling element  32  that extends to a substantially cylindrical cap bottom surface  34 , a substantially cylindrical primer end  36  positioned opposite the substantially cylindrical cap bottom surface  34 , a primer recess  38  in the substantially cylindrical primer end  36  that extends toward the substantially cylindrical cap bottom surface  34 , a primer flash hole  40  positioned in the primer recess  38  to extend through the substantially cylindrical cap bottom surface  34 , and a flange  39  that extends circumferentially about an outer edge of the substantially cylindrical primer end  36 ;   positioning the cap coupling segment  30  within the substantially cylindrical cartridge coupling element  32 ;   compressing the cap coupling segment  30  between the substantially cylindrical retaining side wall  44  and the substantially cylindrical cartridge coupling element  32 ;   connecting at least partially the cartridge coupling element  32  to the retaining cap cavity  50 , wherein the primer flash hole  40  and the retaining cap aperture  52  are at least partially aligned.   
     
     
         11 . The method of forming an ammunition cartridge from a polymer of  claim 10 , further comprising the step of at least partially filling the retaining cap cavity  50  with the cap coupling segment  30 . 
     
     
         12 . The method of forming an ammunition cartridge from a polymer of  claim 10 , wherein the polymer selected from the group consisting of nylon, including nylon 6, nylon copolymers and terpolymers, nylon 6,10 and nylon 6,12, long-chain nylon chemistry alternatives to nylon 11 and nylon 12, as well as a broad variety of compounded nylon materials, 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-butadinen-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, polyphenylsulfone, 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 crosslinked polymers. 
     
     
         13 . The method of forming an ammunition cartridge from a polymer of  claim 9 , further comprising the step of securing a primer into the primer recess  38 ; depositing a propellant into the polymer cartridge  12 ; and positioning a projectile in the projectile aperture  22 . 
     
     
         14 . The method of forming an ammunition cartridge from a polymer of  claim 9 , wherein the retaining cap bottom surface  48  is connected to the cap bottom surface  34  by a staking, weld, braze, solder, or an adhesive. 
     
     
         15 . A metal cap for a polymer ammunition cartridge comprising:
 a substantially cylindrical cartridge cap  18  comprising a substantially cylindrical cartridge coupling element  32  that extends to a substantially cylindrical cap bottom surface  34 , a substantially cylindrical primer end  36  positioned opposite the substantially cylindrical cap bottom surface  34 , a primer recess  38  in the substantially cylindrical primer end  36  that extends toward the substantially cylindrical cap bottom surface  34 , a primer flash hole  40  positioned in the primer recess  38  to extend through the substantially cylindrical cap bottom surface  34 , and a flange  39  that extends circumferentially about an outer edge of the substantially cylindrical primer end  36 ; and   a retaining cap  42  comprising a substantially cylindrical retaining side wall  44  extending to a retaining cap bottom surface  48 , a retaining cap cavity  50  positioned about the substantially cylindrical retaining side wall  44 , and a retaining cap aperture  52  extending through the retaining cap bottom surface  48 , wherein the substantially cylindrical retaining side wall  44  is adapted to be positioned within a polymer cartridge  12 ; and   wherein the substantially cylindrical cartridge coupling element  32  is adapted to fit within an cap coupling segment  30  so that the cap coupling segment  30  is compressed between the substantially cylindrical retaining side wall  44  and the substantially cylindrical cartridge coupling element  32  and the retaining cap bottom surface  48  is at least partially connected to the cap bottom surface  34  such that the primer flash hole  40  and the retaining cap aperture  52  are at least partially aligned.   
     
     
         16 . The cap of  claim 15 , wherein the metal cap comprises aluminum, brass, copper, copper alloys, nickel, nickel alloys, stainless steel, steel or even an engineered resin with enough tensile strength. For example, substantially cylindrical cartridge cap  18  may be formed from aluminum includes grade 7050 aluminum, grade 7075 aluminum, grade 7158 aluminum, grade 6160 aluminum, stainless steels include grade 301 stainless steel, grade 302 stainless steel, grade 303 stainless steel, grade 304 stainless steel, grade 309 stainless steel, grade 316 stainless steel, grade 317 stainless steel, grade 321 stainless steel, grade 347 stainless steel, grade 405 stainless steel, grade 408 stainless steel, grade 409 stainless steel, grade 420 stainless steel, grade 430 stainless steel, grade 434 stainless steel, grade 436 stainless steel, grade 442 stainless steel, grade 444 stainless steel, grade 410 stainless steel, grade 410s stainless steel, grade 414 stainless steel, grade 416 stainless steel, grade 420 stainless steel, and grade 440 stainless steel; and duplex (ferritic-austenitic) stainless steels include grade 2205 stainless steel, grade 2304 stainless steel, grade 2507 stainless steel, standard duplex steel sometimes called grade EN 1.4462 or 2205, super duplex steel typically grade EN 1.4410; duplex 2507 stainless steel, zeron 100 stainless steel, and lean duplex steel; and precipitation hardening (ph) stainless steels include grade 17-4 stainless steel and grade 15-5 stainless steel. For example the retaining cap  42  may be formed from stainless steels include grade 301 stainless steel, grade 302 stainless steel, grade 303 stainless steel, grade 304 stainless steel, grade 309 stainless steel, grade 316 stainless steel, grade 317 stainless steel, grade 321 stainless steel, grade 347 stainless steel, grade 405 stainless steel, grade 408 stainless steel, grade 409 stainless steel, grade 420 stainless steel, grade 430 stainless steel, grade 434 stainless steel, grade 436 stainless steel, grade 442 stainless steel, grade 444 stainless steel, grade 410 stainless steel, grade 410s stainless steel, grade 414 stainless steel, grade 416 stainless steel, grade 420 stainless steel, and grade 440 stainless steel; and duplex (ferritic-austenitic) stainless steels include grade 2205 stainless steel, grade 2304 stainless steel, and grade 2507 stainless steel; and precipitation hardening (ph) stainless steels include grade 17-4 stainless steel grade 15-5 stainless steel, nickel-copper alloys, nickel-aluminum alloys, nickel-molybdenum alloys, nickel-iron alloys, nickel-cobalt alloys, nickel chromium alloys, nickel-titanium alloys, (e.g., carpenter 20cb-3, haynes 25 (1605), hastelloy b-2, c-276, hastelloy x, inconel 600, inconel 601, inconel 625, inconel 718, incoloy 800, incoloy 825, monel 400, nichrome v, nickel 200, nickel 201), copper-zinc alloys (e.g., astm b36, astm b14, b19, b36, b134, b135), copper-tin-phosphorus alloys, copper-zinc-tin alloys, copper-aluminum alloys (e.g., astm b169 alloy a, b124, b150), copper-beryllium-cobalt or nickel alloys (astm b194, b196, b197), copper-zinc-tin-lead alloys and combinations thereof. 
     
     
         17 . The cap of  claim 15 , wherein the metal cap comprises aluminum, brass, copper, copper alloys, nickel, nickel alloys, stainless steel, steel or an engineered resin.