Reduced energy training cartridge for straight blow back operated firearms

• US 8,327,767 B2
• Filed: 01/27/2011
• Issued: 12/11/2012
• Est. Priority Date: 01/27/2011
• Status: Active Grant

• Current Assignee: General Dynamics Ordnance and Tactical Systems - Canada, Inc. (General Dynamics Corporation)
• Original Assignee: General Dynamics Ordnance and Tactical Systems - Canada, Inc. (General Dynamics Corporation)
• Inventors: Lafortune, Eric
• Primary Examiner(s): KLEIN, GABRIEL J
• Application Number:
  US13/015,241
• Publication Number:
  US 20120192751A1
• Time in Patent Office: 684 Days
• Field of Search: 102/430, 102/439, 102/444, 102/446, 102/447, 102/464, 102/520, 102/521, 102/522
• US Class Current: 102/439
• CPC Class Codes: F42B 5/045 of telescopic type F42B5/184 takes precedence
• CPC Class Codes: F42B 8/02 Cartridges F41A33/02, F42B7/12 take precedence

Abstract

The present invention discloses a reduced energy training cartridge for use in a straight blowback operated firearm having a barrel with firing chamber, the cartridge comprising a cartridge case being defined by a rear portion with an external groove, a front portion having a velocity reduction structure and a wall with an outer surface and an inner surface, a sabot slideably engaged within the cartridge case, the sabot having a rear portion with an outside diameter substantially equal to the inside diameter of the inner surface of the cartridge case and which contains a gas sealing and braking structure and a primer disposed in the rear portion of the cartridge case where, upon percussion of the primer, the cartridge case rapidly slides relative to the sabot until such point when the velocity reduction structure of the cartridge case engages with the sealing and braking structure of the sabot, thereby stopping further movement of the cartridge case relative to the sabot, The present invention also contemplates using a metallic case in combination with a non-metallic or polymer sabot.

Claims

1. A reduced energy training cartridge for use in a straight blowback operated firearm, said cartridge comprising:

a cartridge case being defined by a rear portion with an external groove, a front portion, and an intermediate cylindrical wall;

a velocity reduction structure defined by the front portion of the cartridge case, said velocity reduction structure comprising a frustoconical wall having inner and outer canted surfaces and originating from the intermediate cylindrical wall of the of the cartridge case, said velocity reduction structure further comprising a cylindrical wall, having inner and outer surfaces, originating from the frustoconical wall and defining a front-most surface of the cartridge case, said cylindrical wall of the velocity reduction structure having a smaller outer diameter than said intermediate cylindrical wall;

a sabot slidably engaged within said cartridge case, said sabot having a rear portion, with an outside diameter substantially equal to the inside diameter of said intermediate cylindrical wall of said cartridge case, and a sealing and braking structure, said sealing and braking structure of said sabot interacting with said inner canted surface of said velocity reduction structure of said cartridge case, with the proviso that said inner surface of the cylindrical wall of said velocity reduction structure does not contact said sealing and braking structure of said sabot; and

a primer disposed in said rear portion of said cartridge case;

wherein, upon percussion of said primer, said cartridge case slides relative to said sabot until such point when said inner canted surface of said velocity reduction structure of said cartridge case interacts with said sealing and braking structure of said sabot, thereby stopping further movement of said cartridge case relative to said sabot through said interaction of said sealing and braking structure with said inner canted surface of said velocity reduction structure of said cartridge case and wherein said sealing and braking structure does not contact the inner surface of the cylindrical wall of said velocity reduction structure.

2. The training cartridge of claim 1 wherein said cartridge case is made from a metal or metal alloy.

3. The training cartridge of claim 2 wherein said sabot is made from a non-metallic material.

4. The training cartridge of claim 3 wherein said sabot is made from a polymer.

5. The training cartridge of claim 4 wherein said front portion of said sabot further contains a forward cavity area disposed about the axis of said sabot.

6. The training cartridge of claim 5 wherein said sabot further contains a rear recessed area.

7. The training cartridge of claim 6 wherein said sabot further contains at least one gas passage port connecting said rear recessed area and said forward cavity area.

8. The training cartridge of claim 7 wherein said forward cavity area is adapted to receive a projectile.

9. The training cartridge of claim 8 wherein said cartridge case is sized to operate straight blowback operated firearms.

10. The training cartridge of claim 1 wherein said sabot further comprises a sabot external feature, said sabot external feature starting at a point substantially equal to said cylindrical wall of said velocity reduction structure.

11. The training cartridge of claim 10 wherein said inner canted surface has an angle of slope between 5 degrees and 45 degrees relative to said center line of said cartridge case.

12. The training cartridge of claim 11 wherein said sabot further comprises a sabot external angular or curved feature to aid in the feeding of training cartridges from a firearm magazine to barrel chamber.

13. A reduced energy training cartridge for use in a long-rifle caliber, straight blowback operated firearm, said cartridge comprising:

a cartridge case being defined by a rear portion with an external groove, a front portion, and an intermediate cylindrical wall;

a velocity reduction structure defined by the front portion of the cartridge case, said velocity reduction structure comprising a frustoconical wall having inner and outer canted surfaces and originating from the intermediate cylindrical wall of the of the cartridge case, said velocity reduction structure further comprising a cylindrical wall, having inner and outer surfaces, originating from the frustoconical wall and defining a front-most surface of the cartridge case, said cylindrical wall of the velocity reduction structure having a smaller outer diameter than said intermediate cylindrical wall;

a sabot slidably engaged within said cartridge case, said sabot having a rear portion with an outside diameter substantially equal to the inside diameter of said intermediate cylindrical wall of said cartridge case, a sealing portion, and braking portion, said braking portion of said sabot interacting with said inner canted surface of said velocity reduction structure of said cartridge case, with the proviso that said inner surface of the cylindrical wall of said velocity reduction structure does not contact said braking portion of said sabot; and

a primer disposed in said rear portion of said cartridge case;

wherein, upon percussion of said primer, said cartridge case slides relative to said sabot until such point when said inner canted surface of said velocity reduction structure of said cartridge case interacts with said braking portion of said sabot, thereby stopping further movement of said cartridge case relative to said sabot through said interaction of said braking portion with said inner canted surface of said velocity reduction structure of said cartridge case and wherein said braking portion does not contact the inner surface of the cylindrical wall of said velocity reduction structure.

14. The training cartridge of claim 13 wherein said cartridge case is made from a metal or metal alloy.

15. The training cartridge of claim 14 wherein said sabot is made from a non-metallic material.

16. The training cartridge of claim 15 wherein said sabot is made from a polymer.

17. The training cartridge of claim 16 wherein said front portion of said sabot further contains a forward cavity area disposed about the axis of said sabot.

18. The training cartridge of claim 17 wherein said sabot further contains a rear recessed area.

19. The training cartridge of claim 18 wherein said sabot further contains at least one gas passage port connecting said rear recessed area and said forward cavity area.

20. The training cartridge of claim 19 wherein said forward cavity area is adapted to receive a projectile.

21. The training cartridge of claim 20 wherein said cartridge case is sized to operate straight blowback operated firearms.

22. The training cartridge of claim 13 wherein said sabot further comprises a sabot external feature, said sabot external feature starting at a point substantially equal to said cylindrical wall of said velocity reduction structure.

23. The training cartridge of claim 22 wherein said inner canted surface has an angle of slope between 5 degrees and 45 degrees relative to said center line of said cartridge case.

24. The training cartridge of claim 23 wherein said sabot further comprises a sabot external angular or curved feature to aid in the feeding of training cartridges from a firearm magazine to barrel chamber.