ADJUSTABLE BUTTSTOCK FOR FIREARM

• US 20160202016A1
• Filed: 01/13/2016
• Published: 07/14/2016
• Est. Priority Date: 01/13/2015
• Status: Active Grant

• Current Assignee: Sturm Ruger & Company Incorporated
• Original Assignee: Sturm Ruger & Company Incorporated
• Inventors: Taylor, Adam Jay, Gurney, Mark J., Mather, Jonathan Philip
• Granted Patent: US 9,464,863 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F41C 23/14 Adjustable stock or stock parts, i.e. adaptable to personal requirements, e.g. length, pitch, cast or drop

Abstract

A buttstock includes a mounting extension member attachable to a firearm receiver, an adjustable butt pad for varying the length of the stock, and an adjustable cheek rest for adjusting the height of the stock. The butt pad assembly is attached to the extension member by a laterally compressible clamping member operated by a double-acting cam lever having two locking surfaces and a non-locking release surface. At least one adjustment rail extends forward from the butt pad through opposing movable jaws of the clamping member. The rail can slide forward/rearward to adjust the stock length which is lockable via the cam lever locking surfaces. The cheek rest includes compressible opposing adjustment legs operated by a similarly configured cam lever in one embodiment. The height of the cheek rest may be adjusted and locked in position in a similar manner.

Claims

1. An adjustable buttstock for a firearm, the buttstock comprising:

a longitudinal axis;

an elongated stock mounting extension member configured to mount to the firearm;

a clamping member disposed on the mounting extension member, the clamping member having downwardly extending and opposing first and second jaws;

a butt pad assembly comprising an elongated butt pad and a first adjustment rail protruding axially forward from the butt pad, the first adjustment rail received between the jaws and slidable between a plurality of indexed axial positions for adjusting the length of the buttstock;

the jaws of the clamping member laterally movable together and apart between a locked position lockingly engaging the first adjustment rail in one of the axial positions and an unlocked position partially disengaging the first adjustment rail which allows the rail to slide axially relative to the jaws between the axial positions;

an opening spring biasing the jaws apart;

a double-acting cam lever assembly mechanically coupled to the first and second jaws, the cam lever assembly comprising a cam lever pivotably mounted on the first jaw and including two opposing locking surfaces selectively rotatable into engagement with a bearing surface on the first jaw and a non-locking release surface disposed therebetween;

the cam lever pivotably movable from a center release position to one of two opposing locking positions;

wherein placing the cam lever in the center release position positions the release surface towards the bearing surface on the first jaw and moves the jaws apart to the unlocked position for adjusting the length of the buttstock;

wherein moving the cam lever from the center release position to either of the two locking positions engages one of the locking surfaces with the bearing surface on the first jaw and draws the jaws together to the locked position for fixing the length of the buttstock.

2. The buttstock according to claim 1, wherein the locking surfaces are arcuately shaped and the release surface is flat.

3. The buttstock according to claim 2, wherein the bearing surface is formed on a washer coupled to the first jaw.

4. The buttstock according to claim 1, wherein the cam lever assembly further comprises a transversely movable coupling shaft extending laterally between the first and second jaws, the coupling shaft operably coupling the cam lever to the second jaw for moving the jaws together or apart via pivoting the cam lever.

5. The buttstock according to claim 4, wherein the first and second jaws are both molded or cast as an integral unitary structural part of the clamping member.

6. The buttstock according to claim 5, wherein the second jaw clamping member includes a non-detachable upper portion and a detachable lower locking piece movably coupled to the upper portion, the locking piece connected to the coupling shaft and movable towards and away from the first jaw independently of the upper portion.

7. The buttstock according to claim 6, wherein the locking piece includes a first locking protrusion and the first adjustment rail includes a plurality of longitudinally arranged index grooves, the locking protrusions selectively lockingly engage one of the index grooves on the first adjustment rail when the jaws are in the locked position.

8. The buttstock according to claim 1, further comprising a longitudinally-extending stabilizing rod having a front end attachable to the firearm and a rear end coupled to the butt pad assembly.

9. The buttstock according to claim 1, wherein the stabilizing rod and mounting extension member are received in complementary configured sockets formed in the clamping member.

10. The buttstock assembly according to claim 9, further comprising a threaded cross bolt extending laterally between the first and second jaws, the cross bolt being tightened to apply a compressive clamping force on the mounting extension member and stabilizing rod for securement to the clamping member.

11. The buttstock according to claim 10, wherein the cross bolt extends through a transverse hole in the stabilizing rod to lock the stabilizing rod to the clamping member.

12. The buttstock according to claim 4, wherein tension in the cam lever assembly is adjusted by rotating a finger nut disposed on an end of the coupling shaft at the second jaw, the finger nut including a plurality of radially extending detents which alternatingly engage a raised rib formed on a washer disposed on the second jaw.

13. The buttstock according to claim 1, further comprising:

a cheek rest movably coupled to the upper adjustment rail, the cheek rest adjustable in height with respect to the mounting extension member, the cheek rest including first and second adjustment legs extending downwards from opposing lateral sides of an arcuately curved top of the cheek rest;

a pair of vertically extending toothed racks formed on each adjustment leg;

a first toothed washer arranged on the first adjustment leg, the first washer comprising a first row of teeth and a second row of teeth engaging the pair of toothed racks on the first adjustment leg;

a first spring biasing the first toothed washer outwards for disengaging the toothed racks on the first adjustment leg from the first and second rows of teeth on the first washer;

a double-acting second cam lever assembly mechanically coupled to the first and second adjustment legs, the second cam lever assembly comprising a second cam lever mounted on the first adjustment leg, the second cam lever including an elongated operating handle and a cam head comprising two opposing locking surfaces and a non-locking release surface disposed therebetween;

the second cam lever pivotably movable from a center release position to one of two opposite locking positions;

wherein placing the second cam lever in the center release position disengages the first and second rows of teeth on the first washer from the toothed racks on the first adjustment leg to enable the height of the cheek rest to be adjusted;

wherein moving the second cam lever from the center release position to either of the two opposite locking positions engages the first and second rows of teeth on the first washer with the toothed racks on the first adjustment leg to fix the height of the cheek rest.

14. The buttstock according to claim 13, wherein the first adjustment rail extends longitudinally between opposing first and second bearing blocks disposed inside the cheek rest, the first bearing block biased into engagement with the first adjustment rail by the first spring, and the second bearing block biased into engagement with the first adjustment rail by a second spring.

15. The buttstock according to claim 14, wherein the second cam lever assembly further comprises a transversely movable coupling shaft extending laterally between the first and second adjustment legs, the coupling shaft operably coupling the cam lever to the second adjustment leg for moving the adjustment legs together or apart via pivoting the cam lever.

16. The buttstock according to claim 15, wherein tension in the second cam lever assembly is adjusted by rotating a finger nut disposed on an end of the coupling shaft at the second adjustment leg, the finger nut including a plurality of radially extending detents which alternatingly engage a raised rib formed on the second washer.

17. An adjustable buttstock for a firearm, the buttstock comprising:

a longitudinal axis;

an elongated mounting extension member configured to mount to the firearm;

a clamping member disposed on the mounting extension member, the clamping member having downwardly extending and opposing first and second jaws;

a butt pad assembly comprising a butt pad;

an upper adjustment rail protruding axially forward from the butt pad assembly;

a lower adjustment rail protruding axially forward from the butt pad assembly;

the upper and lower adjustment rails received between the jaws and slidable between a plurality of indexed axial positions for adjusting the length of the buttstock;

a plurality of longitudinally spaced apart index grooves disposed on the upper or lower adjustment rail;

a double-acting cam lever pivotably mounted on the first jaw, the cam lever comprising an elongated operating handle extending from an adjoining cam head engaging a bearing surface formed on the first jaw;

a coupling shaft extending laterally through the clamping member, the coupling shaft coupled between the cam lever and a movable locking piece of the second jaw, the locking piece including a first locking protrusion selectively engageable with the index grooves;

the locking piece laterally movable inwards and outwards with respect to the first jaw between a locked position locking the adjustment rails in one of the axial positions and an unlocked position allowing the adjustment rails to slide axially relative to the jaws between the axial positions;

the cam lever pivotably movable from a center release position to one of two opposite locking positions on either side of the center release position;

wherein placing the cam lever in the center release position moves the locking piece outward to the unlocked position in which the first locking protrusion at least partially disengages the index grooves for adjusting the length of the buttstock; and

wherein moving the cam lever from the center release position to either of the two side locking positions draws the locking piece inward to the locked position in which the first locking protrusion engages the index grooves for fixing the length of the buttstock.

18. The buttstock according to claim 17, wherein both the upper and lower adjustment rails include a plurality of longitudinally spaced apart index grooves, the locking piece including a second locking protrusion, the first and second locking protrusions selectively engageable with the index grooves on the upper adjustment rail and lower adjustment rail.

19. An adjustable buttstock for a firearm, the buttstock comprising:

a longitudinal axis;

an elongated mounting extension member configured to mount to the firearm;

a clamping member fixedly attached to the mounting extension member, the clamping member having downwardly extending first and second jaws;

a butt pad assembly movably coupled to the clamping member, the butt pad assembly comprising parallel longitudinally-extending upper and lower adjustment rails, the upper and lower adjustment rails each received between the jaws and slidable between a plurality of indexed axial positions comprised of longitudinally spaced apart grooves on the adjustment rails for adjusting the length of the buttstock;

the second jaw including an upper portion formed integrally with the first jaw and a removable lower locking piece comprising locking protrusions selectively engageable with the grooves of the upper and lower adjustment rails, the locking piece slidable laterally inwards and outwards with respect to the upper portion of the second jaw between a locked position lockingly engaging the adjustment rails in one of the indexed axial positions and an unlocked position partially disengaging the adjustment rails to allow the rails to slide axially relative to the jaws between the axial positions;

a double-acting first cam lever mechanically coupled to the first jaw and locking piece of the second jaw, the first cam lever pivotably movable between two opposing locking positions located at least 180 degrees apart and a center release position therebetween, the first cam lever operable to selectively move the locking piece between the unlocked and locked positions by pivoting the cam lever respectively from the release position to either of the locking positions;

a cheek rest coupled to the upper adjustment rail, the cheek rest adjustable in height with respect to the mounting extension member, the cheek rest including first and second adjustment legs extending downwards from opposing lateral sides of an arcuately curved top of the cheek rest;

the first adjustment leg including a pair of vertically extending toothed racks;

a first toothed washer comprising dual linear arrays of teeth engageable with the toothed racks on the first adjustment leg;

a first spring biasing the first toothed washer outwards for disengaging the toothed racks on the first adjustment leg from the arrays of teeth on the first washer;

a double-acting second cam lever mechanically coupled to the first and second adjustment legs, the second cam lever pivotably movable between two opposing locking positions located at least 180 degrees apart and a center release position therebetween;

the second cam lever operable to selectively move the cheek rest between (i) a locked position in which the linear arrays of teeth on the first toothed washer engages the toothed racks on the first adjustment leg to lock the cheek rest in position, and (ii) an unlocked position in which the linear arrays of teeth on the first toothed washer at least partially disengage the toothed racks on the first adjustment leg to allow sliding adjustment of the height of the cheek rest.

20. The buttstock according to claim 19, wherein:

the first cam lever is pivotably connected to a laterally movable first coupling shaft that mechanically couples the first jaw to locking piece of the second jaw; and

the second cam lever is pivotably connected to a laterally movable second coupling shaft that mechanically couples the first adjustment leg to the second adjustment leg.

21. The buttstock according to claim 20, wherein the second coupling shaft includes an arcuate cutout which is selectively movable between a distal position and a proximate position with respect to the upper adjustment rail;

wherein the upper adjustment rail is slidable through the cheek rest when the cutout is proximate to the upper adjustment rail; and

wherein the upper adjustment rail is not slidable and fixed in position with respect to the cheek rest when the cutout is distal to the upper adjustment rail.

22. The buttstock according to claim 19, wherein the locking piece comprises a key which slidably engages a keyway in the upper portion of the left jaw for guided lateral movement.

23. The buttstock according to claim 19, further comprising a longitudinally-extending stabilizing rod having a front end attachable to the firearm and a rear end coupled to the butt pad assembly.

24. The buttstock according to claim 19, wherein the cheek rest includes an opposing pair of bearing blocks coupled to the adjustment legs that engage opposite sides of the upper adjustment rail.

25. The buttstock according to claim 24, wherein the first spring and a second springs bias the bearing blocks into engagement with upper adjustment rail.

26. The buttstock according to claim 19, wherein the cheek rest is movable on the upper adjustment rail to different axial positions.