May 5, 2026

US12618625 - Compact stock for AR-style firearms

A compact stock for an AR-style firearm includes a receiver extension configured to attach to a lower receiver, a buffer assembly receivable in the receiver extension, a buffer biasing member receivable in the receiver extension, and a buffer locking mechanism. The buffer assembly is configured to reciprocate between a retracted position wherein the buffer assembly is contained within the receiver extension, and an extended position wherein the buffer assembly is in-battery within an upper receiver. The buffer biasing member is configured to bias the buffer assembly toward the extended position. The buffer locking mechanism is configured to selectably retain the buffer assembly and the buffer biasing member within the receiver extension when the buffer assembly is in the retracted position such that the upper receiver is rotatable relative to the lower receiver about a forward take down pin of the firearm unimpeded by the buffer assembly and buffer biasing member.

Assignee: EIGHT HOLDINGS LLC
Inventors: Teodor Puha
Filing date: 2025-01-03

firearmar-stylestock

The patent describes a compact stock designed for AR-style firearms, featuring a receiver extension that allows for the buffer assembly to be retracted or extended while maintaining the ability to rotate the upper receiver relative to the lower receiver. This design includes a locking mechanism to secure the buffer assembly in the retracted position, enhancing the firearm’s compactness and functionality.

Claim 1

1 . A compact stock for an AR firearm, comprising: a housing configured to be engaged with a lower receiver of the firearm, the housing comprising a longitudinal through hole that comprises an angled side wall, at least a portion of which angled sidewall defines a first mating surface; and a receiver extension configured to be received through the through hole of the housing and to threadingly engage the lower receiver, the receiver extension comprising an annular protrusion that forms a conical frustrum having a flat front face, a flat rear face, and an angled side wall, at least a portion of which angled sidewall defines a second mating surface; wherein the second mating surface matingly engages the first mating surface to axially secure the housing to the lower receiver when the receiver extension is received in the through hole of the housing and threadingly engaged with the lower receiver. a housing configured to be engaged with a lower receiver of the firearm, the housing comprising a longitudinal through hole that comprises an angled side wall, at least a portion of which angled sidewall defines a first mating surface; and a receiver extension configured to be received through the through hole of the housing and to threadingly engage the lower receiver, the receiver extension comprising an annular protrusion that forms a conical frustrum having a flat front face, a flat rear face, and an angled side wall, at least a portion of which angled sidewall defines a second mating surface; wherein the second mating surface matingly engages the first mating surface to axially secure the housing to the lower receiver when the receiver extension is received in the through hole of the housing and threadingly engaged with the lower receiver.

Google Patents

https://patents.google.com/patent/US12618625

USPTO PDF

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/12618625