Lightweight polymer ammunition cartridge casings

• US 10,352,670 B2
• Filed: 07/01/2014
• Issued: 07/16/2019
• Est. Priority Date: 11/10/2010
• Status: Active Grant

• Current Assignee: Velocity Holdings LLC (Energy Transfer LP)
• Original Assignee: Velocity Holdings LLC (Energy Transfer LP)
• Inventors: Burrow, Lonnie
• Primary Examiner(s): Weber, Jonathan C
• Application Number:
  US14/320,961
• Publication Number:
  US 20160003589A1
• Time in Patent Office: 1,841 Days
• Field of Search: 102466, 102467, 102516, 102517, 102465
• CPC Class Codes: B22F 1/108 Mixtures obtained by warm mixing
• CPC Class Codes: B22F 2998/10 Processes characterised by the sequence of their steps
• CPC Class Codes: B22F 3/004 Filling molds with powder feeding material to presses in general B30B15/302
• CPC Class Codes: B22F 3/10 Sintering only
• CPC Class Codes: B22F 3/1021 Removal of binder or filler removal of binder from ceramics C04B35/638
• CPC Class Codes: B22F 3/1025 not by heating only
• CPC Class Codes: B22F 3/225 by injection molding
• CPC Class Codes: B22F 5/00 Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
• CPC Class Codes: B22F 5/06 of threaded articles, e.g. nuts
• CPC Class Codes: B22F 9/04 starting from solid material, e.g. by crushing, grinding or milling C22C1/1084 takes precedence; crushing, grinding or milling, in general, see the relevant subclasses, e.g. B02C
• CPC Class Codes: C04B 35/64 Burning or sintering processes C04B33/32 takes precedence ; powder metallurgy B22F
• CPC Class Codes: C22C 1/0458 Alloys based on titanium, zirconium or hafnium
• CPC Class Codes: C22C 14/00 Alloys based on titanium
• CPC Class Codes: C22C 33/0257 characterised by the range of the alloying elements
• CPC Class Codes: C22C 33/0285 with Cr, Co, or Ni having a minimum content higher than 5%
• CPC Class Codes: C22C 38/02 containing silicon
• CPC Class Codes: C22C 38/04 containing manganese
• CPC Class Codes: C22C 38/18 containing chromium
• CPC Class Codes: C22C 38/42 with copper
• CPC Class Codes: C22C 38/44 with molybdenum or tungsten
• CPC Class Codes: C22C 38/48 : with niobium or tantalum
• CPC Class Codes: C22C 38/58 : with more than 1.5% by weight of manganese
• CPC Class Codes: F42B 33/00 : Manufacture of ammunition; Dismantling of ammunition; Apparatus therefor F42B5/188 takes precedence; manufacturing processes for hollow charges F42B1/036; manufacture of blasting cartridge initiators F42B3/195
• CPC Class Codes: F42B 33/001 : Devices or processes for assembling ammunition, cartridges or cartridge elements from parts
• CPC Class Codes: F42B 33/02 : Filling cartridges, missiles, or fuzes; Inserting propellant or explosive charges F42B33/004 takes precedence
• CPC Class Codes: F42B 33/04 : Fitting or extracting primers in or from fuzes or charges F42B33/004 takes precedence
• CPC Class Codes: F42B 5/02 : Cartridges, i.e. cases with charge and missile
• CPC Class Codes: F42B 5/025 : characterised by the dimension of the case or the missile
• CPC Class Codes: F42B 5/30 : of plastics , i.e. the cartridge-case tube is of plastics
• CPC Class Codes: F42B 5/307 : formed by assembling several elements
• CPC Class Codes: F42B 5/313 : all elements made of plastics
• CPC Class Codes: F42C 19/0807 : 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 Class Codes: F42C 19/0823 : Primers or igniters for the initiation or the propellant charge in a cartridged ammunition primers for caseless ammunition F42C19/085
• CPC Class Codes: F42C 19/083 : 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

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.

Claims

1. A method of making a substantially cylindrical insert by metal injection molding comprising the steps of:

providing an injection mold of the substantially cylindrical insert, the insert mold 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 to extend through the bottom surface, a groove in the primer recess around the primer flash hole aperture, and a flange that extends circumferentially about an outer edge of the top surface;

providing a molding feedstock;

injection molding the molding feedstock into the injection mold to form an substantially cylindrical insert having a first size;

and

removing the substantially cylindrical insert form the injection mold to form a finished substantially cylindrical insert.

2. The substantially cylindrical insert of claim 1, wherein the molding feedstock comprises a polymer, a stainless steel, a brass, or a ceramic alloy.

3. The substantially cylindrical insert of claim 1, wherein the molding feedstock 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.

4. The metal injection molding substantially cylindrical insert of claim 3.

5. The substantially cylindrical insert of claim 1, wherein the finished substantially cylindrical insert is about 10 percent to about 20 percent smaller than the finished substantially cylindrical insert.

6. The metal injection molding substantially cylindrical insert of claim 5.

7. The metal injection molding substantially cylindrical insert made by the process of claim 1.

8. An ammunition cartridge comprising:

a substantially cylindrical insert made by the process of injection molding comprising the steps of;

providing an injection mold of the substantially cylindrical insert to form a substantially cylindrical insert wherein the substantially cylindrical insert mold comprises 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 to extend through the bottom surface, and a flange that extends circumferentially about an outer edge of the top surface;

providing a feedstock for injection into the injection mold;

injecting the feedstock into the injection mold to form an substantially cylindrical insert; and

removing the finished substantially cylindrical insert from the injection mold;

a substantially cylindrical polymeric middle body having a connection end and a second end that is molded over the substantially cylindrical insert and into the primer flash hole aperture;

a nose comprising a bullet aperture for receiving a projectile, connected to a neck that extends to a shoulder that adapts to connect to the connection end,

wherein a propellant chamber is formed between the bullet aperture and the primer flash hole aperture.

9. The ammunition cartridge of claim 8, wherein the substantially cylindrical polymeric middle body comprise a nylon polymer.

10. The ammunition cartridge of claim 8, wherein the nose is adhesively fitted to the substantially cylindrical polymeric middle body.

11. The ammunition cartridge of claim 8, wherein the nose is adhesively fitted to the substantially cylindrical polymeric middle body with a curable polymer adhesive.

12. The ammunition cartridge of claim 8, wherein the substantially cylindrical insert further comprises a coating to adjust the shrinkage.

13. The ammunition cartridge of claim 8, wherein the bullet aperture comprises a first and a second mechanical interlock for engagement of a bullet.

14. The ammunition cartridge of claim 8, wherein the bullet aperture comprises one or more cannelures formed on an inner circumferential surface of the forward opening end.

15. The ammunition cartridge of claim 8, wherein the bullet aperture comprises one, two, three, or more annular rings that mate with one, two, three, or more corresponding annular grooves positioned on a bullet.

16. The ammunition cartridge of claim 8, wherein a bullet is adhesively fitted to the forward opening end.