Jun 17, 2025

US12332016 - 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.

Assignee: Magpul Industries Corp.
Inventors: Duane Liptak, Timothy Eric Roberts
Filing date: 2022-02-10

firearmstockarm braceadjustable

The patent describes a firearm stock or arm brace featuring an adjustable length of pull, utilizing a plunger mechanism that interacts with two concentric springs. By pressing buttons on the plunger, users can either adjust the stock’s length or detach it from the firearm’s receiver extension.

Claim 1

A firearm stock comprising: a body comprising: an upper portion comprising an aperture configured to receive a receiver extension of a firearm, a lower portion comprising a lower stock; and a hollow cavity extending through the upper portion and a lower portion of the body and configured to house an outer spring, an inner spring, and a plunger; the plunger slidingly arranged in the hollow cavity, and configured to couple to one or more buttons extending through at least one wall of the hollow cavity, and configured to engage with a locking means on the receiver extension of the firearm; wherein depressing the one or more buttons depresses the plunger to a first distance or a second distance, and wherein depressing the plunger up to the first distance compresses the outer spring, allowing for adjustment of a length of pull by disengaging the plunger from the locking means on the receiver extension and reengaging the plunger with the locking means when the one or more buttons are released, wherein depressing the plunger to a second distance, compresses both the outer spring and the inner spring, thereby allowing for detachment of the firearm stock from the fireman by disengaging the plunger completely from the receiver extension. a body comprising: an upper portion comprising an aperture configured to receive a receiver extension of a firearm, a lower portion comprising a lower stock; and a hollow cavity extending through the upper portion and a lower portion of the body and configured to house an outer spring, an inner spring, and a plunger; an upper portion comprising an aperture configured to receive a receiver extension of a firearm, a lower portion comprising a lower stock; and a hollow cavity extending through the upper portion and a lower portion of the body and configured to house an outer spring, an inner spring, and a plunger; the plunger slidingly arranged in the hollow cavity, and configured to couple to one or more buttons extending through at least one wall of the hollow cavity, and configured to engage with a locking means on the receiver extension of the firearm; wherein depressing the one or more buttons depresses the plunger to a first distance or a second distance, and wherein depressing the plunger up to the first distance compresses the outer spring, allowing for adjustment of a length of pull by disengaging the plunger from the locking means on the receiver extension and reengaging the plunger with the locking means when the one or more buttons are released, wherein depressing the plunger to a second distance, compresses both the outer spring and the inner spring, thereby allowing for detachment of the firearm stock from the fireman by disengaging the plunger completely from the receiver extension.

Google Patents

https://patents.google.com/patent/US12332016

USPTO PDF

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/12332016