Firearm stock or arm brace
This disclosure describes a firearm stock or arm brace with an adjustable length of pull. The stock or arm brace can include a body and lower stock, where the body includes a buffer tube receiving aperture and the lower stock includes a hollow cavity with a plunger and two concentric springs therein. One or more buttons can be affixed to sides of the plunger in the hollow cavity that can be used to depress the plunger against the force of one or both of the springs. One of the two springs may be shorter than the other and have a greater spring constant than the longer spring. Depressing the plunger against the taller spring may allow a user to adjust the length of pull while greater pressure and engagement of the second spring allows the stock or arm brace to be removed from a buffer tube or receiver extension.
1. A firearm stock comprising:
a body comprising a buffer tube aperture;
a lower stock extending below the body and comprising a hollow cavity;
a plunger slidingly arranged in the hollow cavity;
one or more buttons arranged on an outside of the hollow cavity and coupled to the plunger through elongated slots in walls of the hollow cavity;
first and second concentric springs forming a nested pair and arranged in the hollow cavity, wherein the first spring is taller than the second spring, and wherein
depressing the plunger up to a first distance compresses the first spring, and
depressing the plunger past the first distance compresses the first spring and the second spring.
2. The firearm stock of claim 1 , wherein the pair of nested springs are wound in opposing directions.
3. The firearm stock of claim 1 , wherein depressing the plunger up to a first distance disengages the plunger from a locking hole in the buffer tube and allows adjustment of the length of pull.
4. The firearm stock of claim 1 , wherein the first spring is arranged outside the second spring.
5. The firearm stock of claim 1 , wherein the second spring is arranged outside the first spring.
6. The firearm stock of claim 1 , wherein a quick-disconnect socket is arranged on a rear of the firearm stock.
7. A firearm comprising:
a barrel;
a receiver coupled to the barrel;
a buffer tube coupled to the receiver; and
a firearm stock selectively coupled to the buffer tube and comprising:
a body comprising a buffer tube aperture;
a lower stock extending below the body and comprising a hollow cavity;
a plunger slidingly arranged in the hollow cavity;
one or more buttons arranged on an outside of the hollow cavity and coupled to the plunger through elongated slots in walls of the hollow cavity;
first and second concentric springs forming a nested pair and arranged in the hollow cavity, wherein the first spring is taller than the second spring, and wherein
depressing the plunger up to a first distance compresses the first spring, and
depressing the plunger past the first distance compresses the first spring and the second spring.
8. The firearm of claim 7 , wherein the pair of nested springs are wound in opposing directions.
9. The firearm of claim 7 , wherein depressing the plunger up to a first distance disengages the plunger from a locking hole in the buffer tube and allows adjustment of a distance between the firearm stock and the receiver.
10. The firearm of claim 7 , wherein the first spring is arranged outside the second spring.
11. The firearm of claim 7 , wherein the second spring is arranged outside the first spring.
12. The firearm of claim 7 , wherein a quick-disconnect socket is arranged on a rear of the firearm stock.
13. A method of detaching a firearm stock from a buffer tube comprising:
depressing one or more buttons coupled to a plunger in a hollow cavity of the firearm stock, to compress one of two concentric springs in the hollow cavity, and thereby withdrawing the plunger from one of a plurality of lock holes in a bottom of the buffer tube;
sliding the firearm stock along the buffer tube;
releasing the one or more buttons to allow the plunger to enter a different one of the plurality of lock holes;
depressing the one or more buttons to compress both of the two concentric springs and thereby withdrawing the plunger from the different one of the plurality of lock holes in a bottom of the buffer tube; and
sliding the firearm stock along the buffer tube to remove it, wherein the plunger is sufficiently depressed to clear a bottom of the buffer tube.
14. The method of claim 13 , wherein the second spring has a greater spring constant than the first spring.
15. The method of claim 13 , wherein the first spring is arranged around the second spring.
16. The method of claim 13 , wherein second spring is arranged around the first spring.
17. The method of claim 13 , wherein the pair of nested springs are wound in opposing directions.
18. The method of claim 13 , further comprising attaching a sling to a quick disconnect socket on a rear of the firearm stock.