4.6mm small arms ammunition

• US 20040244630A1
• Filed: 04/16/2004
• Published: 12/09/2004
• Est. Priority Date: 03/27/2003
• Status: Active Grant

• Current Assignee: RUAG Ammotec GmbH (Government of Switzerland)
• Original Assignee: BAE Systems Plc
• Inventors: Smith, Adrian David, Booth, Derek, Ashley, Robert
• Granted Patent: US 7,210,411 B2
• Time in Patent Office: Days
• US Class Current: 102/517
• CPC Class Codes: F42B 12/74 of the core or solid body
• CPC Class Codes: F42B 12/82 reducing friction

Abstract

A round of ammunition for firing from a gun having a rifled barrel, especially a small arms weapon. The projectile (1) forming a part of the round is of steel or other material having a Vickers Hardness value not less than 550, and has a coating (13) of copper or copper alloy. The projectile has a forward body portion (9) which has a diameter similar to that of the lands of the rifling, and a rearward body portion (3) having a diameter which is similar to the diameter defined by the roots of the rifling grooves. The coating (13) is of a thickness not less than the depth of the said rifling grooves, so that the rifling engraves the coating but does not significantly engrave the underlying steel or other hard material. The advantages associated with a hard projectile material are thus obtained without substantially increasing barrel wear.

Claims

1. The combination of a gun having a rifled barrel and a round of ammunition;

the rifling of the barrel comprising rifling grooves which are separated by lands extending helically along the length of the barrel;

the round of ammunition comprising a projectile;

the projectile having a body comprising a substantially cylindrical body, and at least one annular groove formed in and encircling the said substantially cylindrical body;

the projectile further being provided with a coating of copper or copper alloy;

wherein the body of the projectile is formed from a metal having a Vickers Hardness of not less than 550, and the coating is of a thickness not less than the depth of the said rifling grooves.

2. A combination according to claim 1 wherein the projectile has an ogival nose portion of the body forward of said forward body portion.

3. A combination according to claim 1 wherein the depth of the said annular groove is between about 1% and 10% of the nominal diameter of the projectile.

4. A combination according to claim 3 wherein the depth of the said annular groove is between about 2% and 6% of the nominal diameter of the projectile.

5. A combination according to claim 1 wherein the projectile body is made of a material selected from the group comprising steel, tungsten, alloys of tungsten, and tungsten carbide.

6. A combination according to claim 1 wherein the thickness of the coating is between 0.07 mm and 0.3 mm.

7. A combination according to claim 1 wherein the thickness of the coating is greater than 0.1 mm.

8. A combination according to claim 1 wherein the projectile has an outer a coating of a material which has a lower coefficient of friction than that of the projectile body.

9. A combination according to claim 7 wherein the said outer coating is of molybdenum disulphide.

10. A combination according to claim 1 wherein the gun and the round of ammunition have a nominal calibre of 20 mm or less.

11. A combination according to claim 10 wherein the said nominal calibre is 9 mm or less.

12. A combination according to claim 11 wherein the said nominal calibre is 4.6 mm.

13. A combination of gun and ammunition according to claim 1 wherein the diameter of the body portion is less than or equal to the diameter defined by the roots of the said rifling grooves.

14. A combination of gun and ammunition according to claim 13 wherein the diameter of the body portion is substantially the same as the diameter defined by the roots of the said rifling grooves.

15. A combination of gun and ammunition according to claim 1 wherein the diameter of the body portion is less than or equal to the diameter defined by the said lands.

16. A combination of gun and ammunition according to claim 15 wherein in the diameter of the forward body portion is substantially the same as the diameter defined by the said lands.

17. A projectile for use in a combination as claimed in claim 1;

the projectile having a body comprising a substantially cylindrical body portion, and at least one annular groove formed in and encircling the said body portion;

the projectile further being provided with a coating of copper or copper alloy;

wherein the body of the projectile is formed from a metal having a Vickers Hardness of not less than 550, and the coating is of a thickness between 0.07 mm and 0.3 mm.

18. A projectile according to claim 17 wherein the depth of the said annular groove is between about 1% ad 10% f the nominal diameter of the projectile.

19. A projectile according to claim 1 wherein the projectile body is made of a material selected from the group comprising steel, tungsten, alloys of tungsten, and tungsten carbide.

20. A projectile according to claim 1 wherein the thickness of the coating is greater than 0.01 m.

21. A projectile according to claim 1 wherein the projectile has an outer coating of a material which has a lower coefficient of friction than that of the projectile body.

22. A projectile according to claim 21 wherein the said outer coating is of molybdenum disulphide.

23. A projectile according to claim 1 having nominal calibre of 9 mm or less.

24. A projectile according to claim 23 wherein the said nominal calibre is 4.6 mm.

25. and 26 (canceled)