IP Library Granted Patent US 12,638,261
Granted Patent B2
US 12,638,261 · App. 18/821,369 · Granted May 26, 2026

Recoil assembly for a machine gun

Inventors: David Luke Steimke (Epping, NH); Jeffery John Melochick (Newmarket, NH); Andrew Phillip Loriot (Somersworth, NH); Jacob Thomas Shawley (Somersworth, NH); Lindsay Lee Bunch (Deerfield, NH)
Assignee: Sig Sauer, Inc.
F41A25/12
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Quick Facts
Patent No.
US 12,638,261
App. No.
18/821,369
Granted
May 26, 2026
Kind
B2
Abstract

A recoil assembly for a rifle includes a barrel assembly, a bolt, bolt actuator, and a buffer assembly. The barrel assembly includes a barrel secured to a barrel extension. The barrel assembly is slidably received in the receiver and the barrel extension is coupled to a hydraulic buffer assembly located below the barrel extension. The hydraulic buffer assembly is configured and arranged to arrest rearward movement of the barrel assembly when the rifle is fired. An op-rod spring is coupled to an op rod extending that can be actuated by a gas piston assembly on the barrel. The op-rod spring is configured and arranged to arrest rearward movement of the bolt assembly.

Claims (37)

1 . A feed assembly for a machine gun, the feed assembly comprising:

a rifle housing defining a longitudinal opening;

a barrel assembly extending along a bore axis and partly received in the longitudinal opening, the barrel assembly including a barrel attached to a barrel extension;

a bolt assembly slidably received in the barrel extension, the bolt assembly including a bolt movably coupled to a bolt actuator and a feed cam guide on the bolt actuator;

a feed tray hingedly attached to the rifle housing and configured to receive belted ammunition from a side of the machine gun;

a pawl arranged and configured to advance the belted ammunition laterally across the feed tray during a firing cycle of the machine gun;

a feed cover hingedly attached to the rifle housing and movable between a closed position and an open position;

a slide on an underside of the feed cover, the slide configured to reciprocate laterally across the feed cover during the firing cycle of the machine gun; and

a feed cam having a distal end portion adjacent the feed tray and positioned to reciprocate the slide when the feed cover is in the closed position, the feed cam having a proximal end portion operably engaging the feed cam guide;

wherein reciprocating axial movement of the bolt actuator causes reciprocating lateral movement of the distal end portion of the feed cam.

2 . The feed assembly of claim 1 , wherein the feed cam guide extends up from a proximal end portion of the bolt actuator.

3 . The feed assembly of claim 2 , wherein the feed cam guide comprises a roller.

4 . The feed assembly of claim 1 , wherein the feed tray is configured to receive the belted ammunition from a left side of the machine gun.

5 . The feed assembly of claim 1 , wherein the feed tray is configured to receive the belted ammunition from a right side of the machine gun.

6 . The feed assembly of claim 1 , wherein the feed cover pivots up and forward to the open position.

7 . The feed assembly of claim 1 , wherein the feed cover is hingedly attached to a front end of the feed tray.

8 . The feed assembly of claim 1 , wherein the feed tray and the feed cover are pivotable about a common hinge pin.

9 . The feed assembly of claim 8 , wherein the common hinge pin extends crosswise to the bore axis.

10 . The feed assembly of claim 1 , further comprising a rammer attached to and extending longitudinally along a top of the bolt, the rammer protruding upward from the bolt and arranged to contact a cartridge on the feed tray.

11 . The feed assembly of claim 10 , wherein the rammer extends longitudinally between lugs on the distal bolt end portion, and wherein the rammer is pivotably attached to the bolt.

12 . The feed assembly of claim 1 , wherein a proximal end of the bolt defines a cavity and the actuator is movably received in the cavity of the bolt.

13 . The feed assembly of claim 1 , wherein the barrel assembly is slidably received in the longitudinal opening.

14 . The feed assembly of claim 13 , wherein the barrel assembly is configured to guide axial movement and rotation of the bolt during the firing cycle.

15 . A machine gun comprising the feed assembly of claim 1 .

16 . A feed assembly for a machine gun, the feed assembly comprising:

a rifle housing defining a longitudinal opening;

a barrel assembly configured to be partly received in the longitudinal opening, the barrel assembly extending along a bore axis and including a barrel connected to a barrel extension;

a bolt assembly configured to be slidably received in the barrel extension, the bolt assembly including a bolt movably coupled to a bolt actuator and a feed cam guide on the bolt actuator;

a feed tray hingedly attached to the rifle housing and configured to receive belted ammunition from a side of the machine gun;

a feed cover hingedly attached to the rifle housing and movable between a closed position and an open position;

a slide on an underside of the feed cover, the slide configured to reciprocate laterally across the feed cover during the firing cycle of the machine gun; and

a feed cam extending rearward from the feed tray, the feed cam having a distal end portion positioned to reciprocate the slide when the feed cover is in the closed position and having a proximal end portion positioned to operatively engage the feed cam guide;

wherein, when the barrel assembly is in the longitudinal opening and the bolt assembly is in the barrel extension, reciprocating axial movement of the bolt actuator causes reciprocating lateral movement of the distal end portion of the feed cam.

17 . The feed assembly of claim 16 , further comprising a pawl coupled to the feed tray, the pawl arranged and configured to advance the belted ammunition laterally across the feed tray during a firing cycle of the machine gun.

18 . The feed assembly of claim 16 , wherein the feed tray and the feed cover are pivotable about a common hinge pin that extends crosswise to the bore axis.

19 . The feed assembly of claim 18 , wherein the feed cam guide is on a proximal end portion of the bolt actuator.

20 . The feed assembly of claim 19 , wherein the feed cam guide comprises a roller.

Assignments (2)
SECURITY INTEREST Recorded Apr 24, 2025
From: SIG SAUER INC.
To: TD BANK, N.A, AS ADMINISTRATIVE AGENT
Reel/Frame 071023/0417 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 3, 2024
From: STEIMKE, DAVID LUKE; MELOCHICK, JEFFERY JOHN; LORIOT, ANDREW PHILLIP; SHAWLEY, JACOB THOMAS; BUNCH, LINDSAY LEE
To: SIG SAUER, INC.
Reel/Frame 068470/0420 →
Continuity (5)
Continuation 18179673 · Mar 7, 2023
Continuation 17545351 · Dec 8, 2021
Continuation 16394874 · Apr 25, 2019
Provisional Application 62662603 · Apr 25, 2018
Related Publication 20240418471A1 · Dec 19, 2024
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