Bolt assembly for a firearm

• US 7,886,470 B1
• Filed: 03/28/2008
• Issued: 02/15/2011
• Est. Priority Date: 12/06/2007
• Status: Active Grant

• Current Assignee: Gerald J. Doiron
• Original Assignee: Gerald J. Doiron
• Inventors: Doiron, Gerald J.
• Primary Examiner(s): ELDRED, JOHN W
• Application Number:
  US12/078,229
• Time in Patent Office: 1,054 Days
• Field of Search: 42/690.2, 42/16, 42/19, 891/80, 891/85
• US Class Current: 42/69.02
• CPC Class Codes: F41A 3/46 mounted on the bolt F41A3/48 takes precedence

Abstract

A method of assembling a firearm is provided. The method includes providing a bolt assembly that includes a bolt carrier that includes a cammed slot and a first passage, a bolt member slidably coupled to the bolt carrier and positioned within the first passage, the bolt member includes at least one aperture and a second passage, a piston member slidably coupled to the bolt member and positioned within the second passage, the piston member includes an elongated slot and a third passage, wherein the elongated slot includes a first length, and a cam pin slidably coupled to at least one of the bolt carrier, the bolt member and the piston member, the cam pin includes a fourth passage; and coupling the bolt assembly within a cavity of the firearm such that the bolt assembly is slidably coupled to an upper receiver of the firearm.

Claims

1. A method of assembling a firearm, said method comprising:

providing a bolt assembly that includes a bolt carrier that includes a cammed slot and a first passage, a bolt member slidably coupled to the bolt carrier and positioned within the first passage, the bolt member includes at least one aperture and a second passage, a piston member slidably coupled to the bolt member and positioned within the second passage, the piston member includes an elongated slot and a third passage, wherein the elongated slot includes a first length, and a cam pin slidably coupled to at least one of the bolt carrier, the bolt member and the piston member, the cam pin includes a fourth passage; and

coupling the bolt assembly within a cavity of the firearm such that the bolt assembly is slidably coupled to an upper receiver of the firearm.

2. A method in accordance with claim 1 further comprising coupling a firing pin within at least one of the third passage and the fourth passage, such that the firing pin is slidably coupled to at least one of the piston member and the cam pin.

3. A method in accordance with claim 1 further comprising providing a bolt member that includes a first end that includes at least one flange extending axially away therefrom, wherein the at least one flange includes at least one inner surface oriented at a first angle, a second end that includes a depression defined therein, a plurality of locking lugs extending radially away from the second end, and a chamfer defined within said bolt member that extends between the second passage and the depression.

4. A method in accordance with claim 3 further comprising providing a piston member that includes a tip portion that includes a tip face and an end stop that includes at least one sidewall oriented at a second angle that is substantially identical to said first angle of said at least one flange.

5. A method in accordance with claim 4 further comprising coupling the bolt assembly within the cavity of the firearm such that the tip face of the piston member is positioned adjacent a cartridge primer such that the cartridge primer facilitates actuating the bolt assembly during ignition of a cartridge.

6. A method in accordance with claim 1 further comprising providing a cam pin that includes a substantially cylindrical-shaped body portion and an extension portion that extends away therefrom, wherein the extension portion includes a second length that is substantially shorter than the first length of the elongated slot such that a gap is defined between the extension portion and a wall of the elongated slot.

7. A bolt assembly comprising:

a bolt carrier that comprises a cammed slot and a first passage;

a bolt member slidably coupled to said bolt carrier and positioned within said first passage, said bolt member comprises at least one aperture and a second passage;

a piston member slidably coupled to said bolt member and positioned within said second passage, said piston member comprises a third passage and an elongated slot that comprises a first length; and

a cam pin slidably coupled to at least one of said bolt carrier, said bolt member and said piston member, said cam pin comprising a fourth passage.

8. A bolt assembly in accordance with claim 7 further comprising a firing pin coupled within at least one of said third passage and said fourth passage, such that said firing pin is slidably coupled to at least one of said piston member and said cam pin.

9. A bolt assembly in accordance with claim 7, said bolt member further comprises:

a first end comprising at least one flange extending axially away therefrom, said at least one flange comprises at least one inner surface oriented at a first angle;

a second end comprising a depression defined therein, a plurality of locking lugs extending radially away from said second end, and a chamfer defined within said bolt member that extends between said second passage and said depression; and

a body portion extending between said first end and said second end.

10. A bolt assembly in accordance with claim 9, said piston member further comprises:

an end stop comprising at least one sidewall oriented at a second angle that is substantially identical to said first angle of said at least one flange to facilitate orientating said piston member with respect to said bolt member;

a tip portion comprising a tip face that facilitates contacting a primer of a cartridge; and

a body portion extending between said end stop and said tip portion.

11. A bolt assembly in accordance with claim 7, said cam pin further comprises a substantially cylindrical-shaped body portion and an extension portion extending away therefrom, said extension portion comprising a second length that is substantially shorter than said first length of said elongated slot.

12. A bolt assembly in accordance with claim 11 further comprising a gap defined between said extension portion and a wall of said elongated slot.

13. A bolt assembly in accordance with claim 7 further comprising a means for actuating said bolt assembly.

14. A firearm comprising:

an upper receiver comprising a cavity defined therein;

a barrel coupled to said upper receiver;

a lower receiver coupled to said upper receiver; and

a bolt assembly slidably coupled to upper receiver and positioned within said cavity, said bolt assembly comprising;

a bolt carrier that comprises a cammed slot and a first passage;

a bolt member slidably coupled to said bolt carrier and positioned within said first passage, said bolt member comprises at least one aperture and a second passage;

a piston member slidably coupled to said bolt member and positioned within said second passage, said piston member comprises a third passage and an elongated slot that comprises a first length; and

a cam pin slidably coupled to at least one of said bolt carrier, said bolt member and said piston member, said cam pin comprising a fourth passage.

15. A firearm in accordance with claim 14 further comprising a firing pin coupled within at least one of said third passage and said fourth passage, such that said firing pin is slidably coupled to at least one of said piston member and said cam pin.

16. A firearm in accordance with claim 14, said bolt member further comprises:

a first end comprising at least one flange extending axially away therefrom, said at least one flange comprises at least one inner surface oriented at a first angle;

a second end comprising a depression defined therein, a plurality of locking lugs extending radially away from said second end, and a chamfer defined within said bolt member that extends between said second passage and said depression; and

a body portion extending between said first end and said second end.

17. A firearm in accordance with claim 16, said piston member further comprises:

an end stop comprising at least one sidewall oriented at a second angle that is substantially identical to said first angle of said at least one flange to facilitate orientating said piston member with respect to said bolt member;

a tip portion comprising a tip face that facilitates contacting a primer of a cartridge; and

a body portion extending between said end stop and said tip portion.

18. A firearm in accordance with claim 14, said cam pin further comprises a substantially cylindrical-shaped body portion and an extension portion extending away therefrom, said extension portion comprising a second length that is substantially shorter than said first length of said elongated slot.

19. A firearm in accordance with claim 18 further comprising a gap defined between said extension portion and a wall of said elongated slot.

20. A firearm in accordance with claim 14 further comprising a means for actuating said bolt assembly.