Spiral case ammunition

• US 8,408,137 B2
• Filed: 05/06/2010
• Issued: 04/02/2013
• Est. Priority Date: 05/06/2009
• Status: Active Grant

• Current Assignee: Vin Battaglia
• Original Assignee: Vin Battaglia
• Inventors: Battaglia, Vin
• Primary Examiner(s): BERGIN, JAMES S
• Application Number:
  US12/775,088
• Publication Number:
  US 20100282112A1
• Time in Patent Office: 1,062 Days
• Field of Search: 102/465, 102/466, 102/467, 102/469, 102/464, 102/430, 102/439, 102/468, 102/470, 102/471, 102/472
• US Class Current: 102/464
• CPC Class Codes: F42B 5/26 Cartridge cases F42B5/18 takes precedence ; manufacturing of cartridge cases B21K21/04
• CPC Class Codes: F42B 5/307 formed by assembling several elements

Abstract

A cartridge for a firearm comprises a case having a base located at one end and a projectile mounted at the other end. A specific volume of propellant is contained in the case and is ignitable via a primer located in the base. The ignition of the propellant causes the projectile to be propelled from the case. The case comprises a wall defining a plurality of circumferential flutes that extend around outer and inner surfaces of the case in a helical or vertical configuration.

Claims

1. A cartridge for a firearm, the cartridge comprising:

a case having a first end and a second end;

a base located at the first end of the case;

a projectile mounted in the second end of the case;

a propellant contained in the case; and

a primer located in the base, the primer being configured to ignite the propellant;

the case comprising a wall defining a plurality of flutes extending from the first end and terminating proximate the second end, the flutes being of a helical configuration, and the flutes extending around an outer surface and an inner surface of the case.

2. The cartridge of claim 1, wherein the second end of the case defines a shoulder portion that tapers into a neck portion, the projectile being mounted in the neck portion, and wherein a thickness of a wall defining the neck portion is greater than a thickness of the wall defining the case.

3. The cartridge of claim 2, wherein the flutes extend from the first end and terminate in the shoulder portion.

4. The cartridge of claim 1, wherein the base is substantially cylindrical in shape and is defined by a wall having a plurality of flutes arranged in a helical configuration on an outer surface thereof, the flutes on the outer surface of the base being configured to engage with the flutes on the inner surface of the first end of the case in an interference fit.

5. The cartridge of claim 1, wherein the base comprises,

a rim located at a rearward end thereof, the rim defining a channel extending circumferentially around the rim, and

a surface defining a hole extending through a bottom surface of the base, the primer being located in the hole and being in communication with the propellant.

6. The cartridge of claim 1, wherein the base comprises a housing and a body located on the housing, the housing comprising a rearward surface and a surface defining a hole extending from the rearward surface through the housing, the primer being located in the hole.

7. The cartridge of claim 1, wherein the base comprises a stamped housing having a plurality of flutes on an outer surface thereof, the flutes being configured to matingly engage the plurality of flutes on the inner surface of the case.

8. The cartridge of claim 7, wherein the plurality of flutes defining the wall of the case and the plurality of flutes on the outer surface of the base are arranged at an angle of about 2 degrees to about 20 degrees relative to an axis defined longitudinally through the case.

9. The cartridge of claim 1, wherein the base includes a forward surface that defines a flash pan having a concave surface that faces the propellant.

10. The cartridge of claim 9, wherein an angle defined by the forward surface of the flash pan is about 10 degrees.

11. The cartridge of claim 1, wherein a material from which the case is fabricated is a polymeric material.

12. The cartridge of claim 11, wherein a polymer of the polymeric material is selected from the group of polymers consisting of polyetheretherketone, polyetherketone, polyphenylsulfone, and combinations of the foregoing.

13. The cartridge of claim 1, wherein a material from which the case is fabricated is one or more of polyetheretherketone and polyetherketone functionalized with carbon nanotubes.

14. The cartridge of claim 13, wherein the carbon nanotubes are present at about 2 wt. % to about 5 wt. %.

15. The cartridge of claim 1, wherein the base and the case are fabricated from a polymeric material and joined in a comelt bond.

16. The cartridge of claim 1, wherein the base and the case are joined using a glue.

17. A cartridge for a firearm, the cartridge comprising:

a case comprising a wall arranged to define a substantially cylindrical member having a forward end, a rearward end, and an inner surface and an outer surface, each of the inner surface and the outer surface defining a plurality of flutes that extend helically along the inner surface and the outer surface;

a projectile located in the forward end of the case;

a base located in the rearward end of the case; and

a propellant located in the case and in communication with and configured to be ignited by a primer in the base.

18. The cartridge of claim 17, wherein the forward end of the cylindrical member includes a shoulder portion and a neck portion located on the shoulder portion, the projectile being retained in the neck portion.

19. The cartridge of claim 17, wherein the base comprises a substantially cylindrical body having an outer surface defining a plurality of flutes that extend helically along the substantially cylindrical body, the plurality of flutes on the outer surface of the base being configured to be received in the plurality of flutes on the inner surface of the cylindrical member of the case in a mechanical interference fit and being joined using a glue.

20. The cartridge of claim 19, wherein the substantially cylindrical body comprises a housing therein, the housing comprising a surface defining a hole extending from a forward portion of the housing to a rearward portion of the housing, the primer being located in the hole.

21. The cartridge of claim 20, wherein the forward portion of the housing includes a flash pan defined by an angled surface configured to direct a flash from an ignition of the primer to the propellant to increase velocity of the projectile in a convergent manner.

22. The cartridge of claim 17, wherein a material from which the case body and the base are fabricated comprises a polymer.

23. The cartridge of claim 22, wherein the polymer is selected from the group consisting of polyetheretherketone, polyetherketone, polyphenylsulfone, and combinations of the foregoing materials.

24. The cartridge of claim 17, wherein the plurality of flutes extend helically along the substantially cylindrical member at an angle of about 2 degrees to about 20 degrees.

25. An assembly for an ammunition cartridge, the assembly comprising:

a substantially cylindrical case comprising a wall configured to define a plurality of flutes extending helically between a rearward end of the case to a forward end of the case, the case comprising a polymeric material, the plurality of flutes being defined on an inner surface of the wall and an outer surface of the wall; and

a base located at the rearward end of the case, the base comprising a housing and a body over-molded on at least a portion thereof, the body comprising the polymeric material, an outer surface of the body defining a plurality of flutes matingly joined to the flutes on the inner surface of the wall of the case in a mechanical interference fit.

26. The assembly of claim 25, wherein the polymeric material comprises one or more of polyetheretherketone and polyetherketone functionalized with carbon nanotubes.

27. The assembly of claim 26, wherein the polymeric material comprises about 2 wt. % to about 5 wt. % carbon nanotubes.

28. The assembly of claim 25, wherein the base comprises a surface defining a hole extending between a forward end and a rearward end of the base through the housing, the hole being configured to receive a primer therein.

29. The assembly of claim 25, wherein a forward end of the housing defines a flash pan defining a forward surface having an angle of about five degrees to about twenty degrees.

30. The assembly of claim 25, wherein the plurality of flutes defined by the outer surface of the base body are matingly joined to the flutes on the inner surface of the wall of the case body using a comelt bond.

31. The assembly of claim 25, wherein the plurality of flutes defined by the outer surface of the body are matingly joined to the flutes on the inner surface of the wall of the case using a glue.

32. The assembly of claim 25, wherein the plurality of flutes defining the wall of the case and the plurality of flutes of the body of the base are arranged at for the caliber from a parallel axis of the vertical centerline of the case to about 20 degrees relative to an axis defined longitudinally through the case.

33. The assembly of claim 25, wherein the housing of the base defines a metallic rim having a channel extending circumferentially therearound, the channel being configured to receive a mechanism for the extraction of the assembly from a firearm.

34. The assembly of claim 25, wherein the flutes defined by the wall of the substantially cylindrical case are configured to provide a selected hoop strength and a selected compressive loading to the case to optimize the wall thickness and greatest potential internal volume for propellant charge weight.