Rifle upper receiver with integral magazine well

• US 8,484,877 B2
• Filed: 10/23/2009
• Issued: 07/16/2013
• Est. Priority Date: 10/23/2009
• Status: Active Grant

• Current Assignee: Michael Dwain Zimmerman
• Original Assignee: Michael Dwain Zimmerman
• Inventors: Zimmerman, Michael Dwain
• Primary Examiner(s): CLEMENT, MICHELLE RENEE
• Application Number:
  US12/589,457
• Publication Number:
  US 20110094136A1
• Time in Patent Office: 1,362 Days
• Field of Search: 42/750.1, 42/710.1, 42/750.3, 42/750.2, 42/16, 42/6
• US Class Current: 42/75.01
• CPC Class Codes: B21C 23/14 Making other products
• CPC Class Codes: F41A 21/484 using interlocking means, e.g. by sliding pins
• CPC Class Codes: F41A 3/66 Breech housings or frames; Receivers
• CPC Class Codes: F41C 23/16 Forestocks; Handgrips; Hand guards pump-action guns F41C7/02

Abstract

Rifle upper receivers with integral magazine wells include an extruded elongate inverted U-shaped channel with an interior bore. The interior of the channel has elements formed as surfaces of extrusion. The surfaces of extrusion provide guidance and support for a magazine and trigger guard assembly pins. The present invention is manufactured by extruding an elongate tube in a closed-box profile with an interior bore, milling a series of slots into the top of the tube, machining a bottom channel opening by removing portions of the bottom of the tube, machining holes in the sides of the tube, and machining a recess in the top of the interior of the tube.

Claims

1. A rifle upper receiver with integral magazine well comprising:

an extruded elongate inverted U-shaped channel with an interior bore;

the channel having a top, a bottom, a left side, and a right side;

the channel having front, rear, and bottom openings;

the channel having an interior with elements formed as surfaces of extrusion;

the surfaces of extrusion providing guidance and support for a magazine and trigger guard assembly pins;

a recess in the top of the interior bore of the tube;

the recess receiving a recoil lug;

the recoil lug protruding from the top of a trunnion;

a plurality of trunnion attachment holes in the left side and right side of the channel;

the trunnion attachment holes receiving trunnion attachment screws; and

the trunnion screws removably securing the trunnion to the channel.

2. The upper receiver of claim 1, further comprising:

a plurality of trigger guard assembly mounting holes in the left side and right side of channel;

the trigger guard assembly mounting holes receiving trigger guard assembly attachment pins; and

the trigger guard assembly attachment pins removably securing a trigger guard assembly to the channel.

3. The upper receiver of claim 1, further comprising:

a guide rod channel defined by a slot in the top of one side of the channel;

the guide rod channel receiving a guide rod and spring; and

the guide rod guiding the reciprocating motion of a bolt assembly within the interior bore of the channel.

4. The upper receiver of claim 1, further comprising:

an ejection port defined by a bore in one side of the channel; and

the ejection port being in communication with the interior bore of the channel.

5. The upper receiver of claim 1, further comprising the top of the channel comprising a military specification top rail.

6. The upper receiver of claim 1, further comprising:

a plurality of bottom rail mounting holes in the bottom of the left side and right side of the channel;

the bottom rail mounting holes receiving bottom rail attachment screws;

the bottom rail attachment screws removably securing a bottom rail to the channel; and

the bottom rail removably covering a portion of the bottom of the channel.

7. The upper receiver of claim 1, further comprising:

the trunnion having a barrel tenon bore; and

the barrel tenon bore receiving a barrel tenon attached to a barrel.

8. The upper receiver of claim 1, further comprising:

the trunnion having a magazine pin hole; and

the magazine pin hole receiving a magazine pin protruding from a magazine.

9. The upper receiver of claim 7, further comprising:

the trunnion having a barrel retainer screw hole;

the barrel retainer screw bole threadedly receiving a barrel retainer screw;

the barrel retainer screw attaching a barrel retainer to the trunnion;

the barrel retainer cantilevering the barrel into place within the tube, leaving the barrel projecting outward with an unsupported forward end.

10. The upper receiver of claim 1, further comprising:

a recoil pin mounting hole in the left side and the right side of the channel;

the recoil pin mounting holes receiving a recoil stop pin; and

the recoil stop pin limiting rearward motion of a bolt assembly within the interior bore of the channel.

11. A rifle upper receiver comprising:

an extruded elongate inverted U-shaped channel with an interior bore;

the channel having a top, a bottom, a left side, and a right side;

the channel having front, rear, and bottom openings;

the channel having an interior with elements formed as surfaces of extrusion;

wherein the surfaces of extrusion provide opposed magazine support surfaces for a magazine;

wherein the surfaces of extrusion provide opposed retention surfaces for trigger guard assembly pins; and

wherein the retention surfaces include two pairs of upper pin retention rails, each pair having two members separated by a channel.

12. The upper receiver of claim 11, wherein the magazine support surfaces face each other.

13. The upper receiver of claim 11, wherein at least a portion of the magazine support surfaces are parallel to each other.

14. The upper receiver of claim 11, wherein one of the opposed magazine support surfaces includes two faces that meet at right angles.

15. The upper receiver of claim 11, wherein one of the opposed magazine support surfaces includes two upper faces that meet at right angles, a concave portion that hangs beneath the two upper faces, and a lower face that connects the concave portion to a side of the upper receiver.

16. The upper receiver of claim 11, wherein the retention surfaces face each other.

17. The upper receiver of claim 11, wherein the retention surfaces are parallel to each other.

18. A rifle upper receiver comprising:

an extruded elongate inverted U-shaped channel with an interior bore;

the channel having a top, a bottom, a left side, and a right side;

the channel having front, rear, and bottom openings;

the channel having an interior with elements formed as surfaces of extrusion;

wherein the surfaces of extrusion provide opposed magazine support surfaces for a magazine;

wherein the surfaces of extrusion provide opposed retention surfaces for trigger guard assembly pins; and

wherein the retention surfaces include two lower pin retention rails that protrude upwards from the bottom of the channel.

19. The upper receiver of claim 18, wherein the magazine support surfaces face each other.

20. The upper receiver of claim 18, wherein the retention surfaces face each other.