Self loading firearm bolt carrier with integral carrier key and angled strike face

• US 20120152105A1
• Filed: 05/14/2010
• Published: 06/21/2012
• Est. Priority Date: 05/14/2010
• Status: Active Grant

• Current Assignee: LWRC International LLC
• Original Assignee: LWRC International LLC
• Inventors: Gomez, Jesus S., Miller, Jason Lee, Schilling, Robert S., Llewellyn, Michael R.
• Granted Patent: US 8,387,513 B2
• Time in Patent Office: Days
• US Class Current: 89/191.01
• CPC Class Codes: F41A 5/20 using a gas piston arranged concentrically around the barrel

Abstract

A bolt carrier for use with the AR15/M16 family of firearms is provided. The bolt carrier includes an integrally formed carrier key and spherical strike face surrounded by a cylindrical counterbore made with a downward angle to act against the tilting force imparted by the operating rod of the firearm'"'"'s gas operating system. The outer surface of the carrier includes upper and lower running rails that all extend fully to the front face of the carrier to lengthen the carrier'"'"'s rail support or bearing surfaces against the receiver. To improve the robust operation of the firearm in over the beach operations, the bottom and rear of the receiver extension has drain holes formed through which water is forced out of the receiver extension by the reciprocating action of the bolt carrier when the weapon is fired. In dry conditions, the firearm is protected against jamming by relief or sand cuts formed in the running rails which provide recesses for dirt to accumulate during operation so as not to interfere with movement of the bolt assembly.

Claims

1. A bolt carrier for a gas-operated automatic or semi-automatic firearm comprising an elongated generally cylindrical body having a forward end with a front face, a rearward end, an upper exterior surface, and a lower exterior surface, said upper exterior surface having an integrally formed carrier key and strike face with a counterbore to support an operating rod in contact with the strike face, said strike face and counterbore being downwardly angled.

2. The bolt carrier as set forth in claim 1, wherein the strike face and counterbore are angled downwardly at an angle of between about 0.05 degrees and about 5.0 degrees.

3. The bolt carrier as set forth in claim 2, wherein the bolt carrier further includes upper rails and lower rails for contacting a receiver of said weapon, said upper rails extending up to said front face.

4. The bolt carrier as set forth in claim 3, wherein said rails have debris relief cuts formed therein to provide a recess for dirt and debris to accumulate without interfering with bolt carrier function.

5. The bolt carrier as set forth in claim 1, in combination with a gas-operated automatic or semi-automatic firearm having a receiver extension with drain holes formed therein, a rear end of said bolt carrier including an enlarged diameter boss with flutes formed therein for engaging the receiver extension to reduce carrier tilt and to provide, in conjunction with the receiver extension drain holes, for water removal from the receiver extension during firing.

6. The bolt carrier and firearm as set forth in claim 5, wherein said firearm gas-operating system includes an operating rod made of superalloy.

7. A gas-operated automatic or semi-automatic bolt action firearm comprising:

a receiver;

a barrel coupled to said receiver;

a bolt carrier with a bolt assembly configured to be received within said receiver;

a gas operating system with an operating rod for displacing the bolt assembly when the firearm is fired; and

said bolt carrier including upper rails and lower rails for contacting said receiver, both said upper and said lower rails extending up to a front face of said bolt carrier.

8. The automatic or semi-automatic bolt action firearm as set forth in claim 7, wherein said rails have debris relief cuts formed therein to provide a recess for dirt and debris to accumulate during operation of the firearm without interfering with bolt carrier function.

9. The automatic or semi-automatic bolt action firearm as set forth in claim 7, wherein said bolt carrier includes an integrally formed carrier key having a strike face oriented to be contacted by said operating rod when the firearm is fired to effect said bolt assembly displacement.

10. The automatic or semi-automatic bolt action firearm as set forth in claim 9, wherein the carrier key strike face is angled downwardly at between about 0.05 degrees and about 5.0 degrees.

11. The automatic or semi-automatic bolt action firearm as set forth in claim 7, wherein said bolt carrier includes a charging handle engagement shelf adjacent a front face of said carrier, said upper rails extending to said front face on either side of said shelf.

13. The automatic or semi-automatic bolt action firearm as set forth in claim 7, wherein said receiver extension includes drain holes in a bottom and rear thereof through which water is pumped out of the receiver extension by reciprocating action of the bolt carrier as the firearm is fired.

14. The automatic or semi-automatic bolt action firearm as set forth in claim 7, wherein said operating rod is made of super alloy with a nickel content of between about 15% and about 22% by weight of a total material composition and a cobalt content of between about 5% to about 15% by weight of the total material composition.

15. A gas-operated automatic or semi-automatic bolt action firearm comprising:

a receiver and receiver extension;

a barrel coupled to said receiver;

a bolt carrier with a bolt assembly configured to be received within said receiver, said bolt carrier having an enlarged fluted boss at a rear end thereof;

a gas operating system with an operating rod for displacing the bolt assembly when the firearm is fired; and

said receiver extension including drain holes in a bottom and rear thereof through which water is pumped out of the receiver extension by reciprocating action of the bolt carrier during said bolt assembly displacement.

16. The automatic or semi-automatic bolt action firearm as set forth in claim 15, wherein the bolt carrier further includes upper rails and lower rails for contacting the receiver, said upper rails extending up to a front face of said bolt carrier on either side of a charging handle engagement shelf, said rails having debris relief cuts formed therein to provide a recess for dirt and debris to accumulate without interfering with bolt carrier function.

17. The automatic or semi-automatic bolt action firearm as set forth in claim 15, wherein said bolt carrier includes an integrally formed carrier key having a spherical strike face oriented to be contacted by said operating rod when the firearm is fired to effect said bolt assembly displacement, said spherical strike face being surrounded by a cylindrical counterbore, said carrier key strike face and counterbore being angled downwardly at an angle of between about 0.05 degrees and about 5.0 degrees.

20. The automatic or semi-automatic bolt action firearm as set forth in claim 15, wherein said bolt carrier includes an integrally formed carrier key having a spherical strike face oriented to be contacted by said operating rod when the firearm is fired to effect said bolt assembly displacement, said spherical strike face being surrounded by a cylindrical counterbore, said carrier key strike face and counterbore being angled downwardly at an angle of between about 0.05 degrees and about 5.0 degrees.

18. An automatic or semi-automatic bolt action firearm comprising:

a receiver;

a barrel coupled to said receiver;

a bolt carrier with a bolt assembly configured to be received within said receiver; and

a gas operating system for displacing the bolt assembly when the firearm is fired, said gas operating system including an operating rod made of super alloy with a nickel content of between about 15% and about 22% by weight of a total material composition and a cobalt content of between about 5% to about 15% by weight of the total material composition.

19. The automatic or semi-automatic bolt action firearm as set forth in claim 18, wherein the bolt carrier further includes upper rails and lower rails for contacting the receiver, said rails having debris relief cuts formed therein to provide a recess for dirt and debris to accumulate without interfering with bolt carrier function.