Magazine for firearm

Patent metadata

Field	Value
Publication number	US-11493293-B2
Application number	US-202017030693-A
Country	US
Kind code	B2
Filing date	Sep 24, 2020
Priority date	Sep 25, 2019
Publication date	Nov 8, 2022
Grant date	Nov 8, 2022

Abstract

A magazine for a firearm comprises a tubular magazine body defining a cavity for holding cartridges, a spring, and a follower biased by the spring for dispensing cartridges from the magazine. A spring base disposed on the body includes a cantilevered resiliently deformable spring arm supporting the spring in one embodiment. The base is held in place by the floor plate. Sliding the floor plate onto the magazine body engages an inclined ramp of the floor plate with spring arm which automatically moves the spring arm from an undeflected to deflected position. When the floor plate is fully coupled to the magazine tube such that the spring arm clears the ramp, the spring arm snaps back to the undeflected position and locks the floor plate in place on the tubular body via interlocked retention features without use of tools.

First claim

What is claimed is:

1. A magazine for a firearm comprising:
an elongated tubular body defining a vertical centerline and an interior cavity configured to hold a stack of ammunition cartridges, the tubular body including a top end, a bottom end, a front wall, a rear wall, and opposed lateral sidewalls extending between the front and rear walls;
a rear portion of the top end of the body further comprising a pair of inwardly protruding cartridge feed lips configured to engage an uppermost cartridge in the stack;
a spring disposed in the cavity;
a follower moveably disposed in the cavity and biased in an upwards direction towards the top end by the spring;
a spring base detachably positioned on the bottom end of the tubular body, the spring base comprising a cantilevered spring arm supporting the spring, the spring arm being resiliently deformable between an undeflected position and a deflected position;
a floor plate slideably engageable with the bottom end of the body which retains the spring base on the tubular body;
wherein the floor plate is configured to automatically move the spring arm from the undeflected position to the deflected position when the floor plate is slid onto the bottom end of the tubular body;
wherein the spring defines a spring axis which is parallel to and offset from the vertical centerline of the body, the spring being configured and operable such that a top end of the spring acts solely on a front portion of the follower forward of the feed lips.

2. The magazine according to claim 1 , wherein the floor plate includes an inclined ramp operable to slideably engage and raise the spring arm from the undeflected position to the deflected position when the floor plate is slid onto the bottom of the tubular body.

3. The magazine according to claim 2 , wherein the inclined ramp is located on a rear portion of the floor plate and slopes in a downward direction from front to rear.

4. The magazine according to claim 2 , wherein the inclined ramp of the floor plate is positioned to the rear of the spring arm when the floor plate is fully mounted on the tubular body of the magazine.

5. The magazine according to claim 4 , wherein the spring is positioned forward of the inclined ramp when the floor plate is fully mounted on the tubular body of the magazine.

6. The magazine according to claim 2 , wherein the inclined ramp defines a flat top sloped surface which engages a complementary angled flat sloped bottom surface section of the spring base forming a flat-to-flat interface therebetween.

7. The magazine according to claim 2 , wherein the spring arm defines a V-shaped locking notch which lockingly engages a complementary configured locking edge of the floor plate forming an interlock which prevents the floor plate from being slideably removed from the tubular body of the magazine.

8. The magazine according to claim 7 , wherein the spring arm is vertically offset from an elongated rear portion of the spring base.

9. The magazine according to claim 8 , wherein the locking notch is formed on an underside of the spring base at a stepped transition between the rear portion of the spring base and the spring arm.

10. The magazine according to claim 7 , wherein the floor plate includes a bottom wall defining an upwardly open recessed receptacle, the spring arm being seated on an upward facing lower surface within the receptacle when the floor plate is fully mounted on the tubular body of the magazine.

11. The magazine according to claim 10 , wherein the bottom wall includes a tooling through hole in the receptacle providing access to the bottom surface of the spring arm for manually moving the spring arm from the undeflected position to the deflected position.

12. The magazine according to claim 10 , wherein the locking notch of the floor plate is defined by a stepped transition between the inclined ramp and the recessed receptacle.

13. The magazine according to claim 1 , wherein the spring arm has a semi-circular configuration.

14. The magazine according to claim 1 , wherein the spring is a helical compression spring with circular coils.

15. The magazine according to claim 14 , wherein the spring arm defines an upward facing spring seating surface which engages and supports a bottom coil of the spring.

16. The magazine according to claim 14 , wherein the spring arm includes a cylindrical spring retention protrusion which engages a bottom end of the spring to retain the spring in position.

17. The magazine according to claim 1 , wherein the spring is located proximate to the front wall of the tubular body.

18. The magazine according to claim 1 , wherein the spring arm engages the spring and extends forwardly from a rear portion of spring base.

19. The magazine according to claim 18 , wherein a rear end of the rear portion of the spring base comprises a raised lip which engages the rear wall of the tubular body of the magazine.

20. The magazine according to claim 2 , wherein the floor plate includes a pair of grooves which slideably engage a corresponding pair of retention flanges on the bottom end of the tubular body.

21. The magazine according to claim 1 , wherein the follower comprises a rear portion, a laterally enlarged front guide disk, and a front stabilizer wall extending downwardly from the guide disk, a gap between the rear portion and the stabilizer wall defining a spring receptacle which receives a top end of the spring.

22. The magazine according to claim 21 , wherein the stabilizer wall extends below the rear portion of the follower.

23. A pistol defining a magazine well configured to receive the magazine according to claim 1 .

24. The magazine according to claim 1 , wherein a bottom end of the spring acts solely on the spring arm of the spring base.

25. The magazine according to claim 1 , wherein the front portion of the follower on which the spring acts is positioned beneath a forward opening in the top end of the body forward of the feed lips.

26. The magazine according to claim 14 , wherein the spring is located adjacent to the front wall of the body and disposed entirely forward of the feed lips.

27. The magazine according to claim 26 , wherein the spring occupies only a front half of the cavity of the magazine.

28. The magazine according to claim 2 , wherein the ramp of the floor plate is horizontally elongated and defines an upward facing sloped surface configured which slideably engages a bottom surface of the spring arm of the spring base.

29. The magazine according to claim 1 , wherein the bottom end of the spring engages a spring seating surface of the spring arm which lies in a horizontal plane lower than an adjoining flat rear portion of the spring base.

30. The magazine according to claim 10 , wherein an automatic snap interlock is automatically formed between the spring arm of the spring base and the receptacle of the floor plate when the floor plate is slid onto the body of the magazine without the use of a tool.

Assignees

• Sturm Ruger & Co

Inventors

• Brown Nathan
• Potter Dwight

Classifications

• F41A9/66 Primary

  Arrangements thereon for charging, i.e. reloading (apparatus or tools for reloading of magazines F41A9/83) · CPC title

• F41A9/65

  Box magazines having a cartridge follower · CPC title

• F41A9/70 Primary

  Arrangements thereon for discharging, e.g. cartridge followers or discharge throats · CPC title

• F41A11/00

  Assembly or disassembly features; Modular concepts; Articulated or collapsible guns (F41A3/64, F41A19/10 - F41A19/15, F41A21/48, F41A25/26 take precedence) · CPC title