Ammunition casing

• US 8,240,252 B2
• Filed: 03/07/2005
• Issued: 08/14/2012
• Est. Priority Date: 03/07/2005
• Status: Active Grant

• Current Assignee: Mississippi Polymer Technologies Incorporated (Solvac SA), Solvay Advanced Polymers LLC (Solvac SA)
• Original Assignee: Solvay Advanced Polymers LLC (Solvac SA)
• Inventors: Maljkovic, Nikica, Rushing, Todd S.
• Primary Examiner(s): Johnson, Stephen M
• Application Number:
  US11/074,616
• Publication Number:
  US 20060207464A1
• Time in Patent Office: 2,717 Days
• Field of Search: 102/466
• US Class Current: 102/466
• CPC Class Codes: C08G 2261/312 Non-condensed aromatic systems, e.g. benzene
• CPC Class Codes: C08L 2666/14 Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
• CPC Class Codes: C08L 65/02 Polyphenylenes
• CPC Class Codes: C08L 69/00 Compositions of polycarbonates; Compositions of derivatives of polycarbonates
• CPC Class Codes: C08L 81/06 Polysulfones; Polyethersulfones
• CPC Class Codes: F42B 5/297 with plastics
• 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

Abstract

An ammunition article is provided which comprises a casing and a cap wherein the casing is formed from a polymeric material that has a room temperature notched Izod impact value greater than about 10 ft lbs/in and then has a ratio of notched Izod impact value at room temperature to notch Izod impact value at about −40° C. of less than about 4.

Claims

1. A 22, .22-250, .223, .243, .25-06, .270, .300, .30-30, .30-40, 30.06, .303, .308, .357, .38, .40, .45, .45-70, .50 BMG, 5.45 mm, 5.56 mm, 6.5 mm, 6.8 mm, 7 mm, 7.62 mm, 8 mm, 12.7 mm, 14.5 mm, 20 mm, 25 mm, 30 mm, or 40 mm caliber ammunition article comprising:

an ammunition casing, the casing defining a generally cylindrical hollow body having first and second ends and consisting of a caselet and a cap;

a propellant disposed and confined within said hollow body and

a primer for disposed at the first end of said casing in combustible communication with said propellant;

wherein the caselet comprises a polymeric material that has a room temperature (about 23°

C.) notched Izod impact strength, measured in accordance with ASTM D256-00, greater than about 10 ft lbs/in and that has a ratio of notched Izod impact strength at room temperature to notched Izod impact strength at about −

40°

C. of less than about 4.

2. An ammunition article according to claim 1 wherein said polymeric material additionally comprises 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.

3. The ammunition article according to claim 1 wherein said polymeric material comprises more than one polymer or copolymer blended or otherwise mixed together.

4. An ammunition article provided in accordance with claim 1 additionally comprising a projectile fitted in the second end.

5. The ammunition article provided in accordance with claim 4 wherein the projectile is secured to the casing by molding the polymeric material around the projectile.

6. The ammunition article provided in accordance with claim 4 wherein the projectile is secured to the casing by mechanical interference.

7. The ammunition article provided in accordance with claim 4 wherein the projectile is secured to the casing by an adhesive.

8. The ammunition article provided in accordance with claim 4 wherein the projectile is secured to the casing by ultrasonic welding.

9. The ammunition article provided in accordance with claim 4 wherein the projectile is secured to the casing by the combination of molding in place and adhesive.

10. The ammunition article provided in accordance with claim 4 wherein the projectile is secured to the casing by hot crimping after the act of molding.

11. The ammunition article of claim 1, wherein said polymeric material is a polymer blend comprising at least two polymers having has a room temperature (about 23°

C.) notched Izod impact strength, measured in accordance with ASTM D256-00, greater than about 10 ft lbs/in in a ratio of notched Izod impact strength at room temperature to notched Izod impact strength at about −

40°

C. of less than about 4; and

wherein at least one of the polymers is a high modulus polymer.

12. The ammunition article according to claim 11 wherein the high modulus polymer is a rigid-rod polyphenylene polymer or copolymer.

13. The ammunition article according to claim 11 wherein the high modulus polymer comprises less than about 24% by weight of the total weight of the polymer material.

14. The ammunition article according to claim 11 wherein the high modulus polymer comprises less than about 10% by weight of the total weight of the polymer material.

15. The ammunition article according to claim 11 wherein the high modulus polymer comprises less than about 5% by weight of the total weight of the polymeric material.

16. The ammunition article according to claim 11 wherein the high modulus polymer comprises less than about 1% by weight of the total weight of the polymeric material.

17. The ammunition article according to claim 11 wherein the high modulus polymer comprises less than about 0.1% by weight of the total weight of the polymeric material.

18. The ammunition article of claim 1, wherein said polymeric material that has a room temperature (about 23°

C.) notched Izod impact strength, measured in accordance with ASTM D256-00, greater than about 12 ft lbs/in and has a ratio of notched Izod impact strength at room temperature to notched Izod impact strength at about −

40°

C. of less than about 4.

19. The ammunition article of claim 1, wherein said polymeric material that has a room temperature (about 23°

C.) notched Izod impact strength, measured in accordance with ASTM D256-00, greater than about 10 ft lbs/in and that has a ratio of notched Izod impact strength at room temperature to notched Izod impact strength at about −

40°

C. of less than about 3.

20. The ammunition article of claim 1, wherein said polymeric material has a room temperature (about 23°

C.) notched Izod impact strength, measured in accordance with ASTM D256-00, greater than about 12 ft lbs/in and that has a ratio of notched Izod impact strength at room temperature to notched Izod impact strength at about −

40°

C. of less than about 3.

21. The ammunition article according to claim 1, wherein said polymeric material that has a room temperature (about 23°

C.) notched Izod impact strength, measured in accordance with ASTM D256-00, greater than about 10 ft lbs/in and has a ratio of notched Izod impact strength at room temperature to notched Izod impact strength at about −

40°

C. of less than about 2.

22. The ammunition article according to claim 1, wherein the casing is comprised of a polymeric material that has a room temperature (about 23°

C.) notched Izod impact strength, measured in accordance with ASTM D256-00, greater than about 12 ft lbs/in and that has a ratio of notched Izod impact strength at room temperature to notched Izod impact strength at about −

40°

C. of less than about 2.

23. The ammunition article according to claim 1, wherein polymeric material comprises polyphenylsulfone.

24. The ammunition article according to claim 1, wherein the polymeric material comprises a blend of polyphenylsufone and a high modulus polymer or copolymer.

25. The ammunition article according to claim 1, wherein the polymeric material comprises a siloxane-modified Bisphenol-A polycarbonate.

26. The ammunition article according to claim 1, wherein the polymeric material comprises a blend of a siloxane-modified Bisphenol-A polycarbonate and a high modulus polymer or copolymer.

27. The ammunition article according to claim 1, wherein the polymeric material comprises a Bisphenol-A polycarbonate with biphenyl linkages.

28. The ammunition article according to claim 1, wherein the polymeric material comprises a blend of a Bisphenol-A polycarbonate with biphenyl linkages and a high modulus polymer or copolymer.

29. The ammunition article according to claim 1, wherein the polymeric material comprises a blend of Bisphenol-A polycarbonate and an acrylic elastomer.

30. The ammunition article according to claim 1, wherein the polymeric material comprises a blend of a Bisphenol-A polycarbonate and acrylic elastomer, and a high modulus polymer or copolymer.

31. The ammunition article according to claim 1, wherein the cap comprises steel.

32. The ammunition article according to claim 1, wherein the cap comprises an aluminum alloy.

33. The ammunition article according to claim 1, wherein the cap comprises brass.

34. The ammunition article according to claim 1, wherein the cap comprises a magnesium alloy.

35. The ammunition article according to claim 1, wherein the cap comprises a polymer.

36. The ammunition article according to claim 1, wherein the caselet is closed at its forward end and contains no projectile.

37. The ammunition article according to claim 1, wherein the polymeric material comprises a polyphenylsulfone and a copolymer comprising the general structural formula:

(—

Ar—

/—

Y—

)_n 

 

(1)

wherein -AR—

is at least 0.1 mol% of the recurring units in (1) and wherein —

Ar—

is at least one arylene or heteroarylene repeat unit selected from the group consisting of;

38. The ammunition article according to claim 37, wherein A is selected from the group consisting of alkyl, aryl, alkyl ketone, aryl ketone, alkoxy, aryloxy, alkylester, arylester, alkylamide and arylamide.

39. The ammunition article according to claim 37, wherein A is selected from the group consisting of acetyl, benzoyl, carbomethoxy, formyl, phenoxy, phenoxybenzoyl, and phenyl.

40. The ammunition article according to claim 37, wherein Y is nil and the copolymer comprises the structure:

41. The ammunition article according to claim 37, wherein Y is nil and the copolymer has a structure selected from the group consisting of the following structures:

42. The ammunition article according to claim 1, wherein the caselet consists of a polymeric material that has a room temperature (about 23°

C.) notched Izod impact strength, measured in accordance with ASTM D256-00, greater than about 10 ft lbs/in and that has a ratio of notched Izod impact strength at room temperature to notched Izod impact strength at about −

40°

C. of less than about 4.

43. The ammunition article according to claim 42, wherein the polymeric material is polyphenylsulfone.

44. The ammunition article according to claim 1, wherein the polymeric material has a flexural modulus of at least 300,000 psi.