Dec 23, 2025

US12504244 - Modular bolt action rifle with bearings

The present disclosure presents a modular bolt action rifle system with roller bearings having an upper receiver assembly housing a barrel, a lower receiver assembly comprising an AR-style fire control system and a magazine well, a bolt carrier group assembly including a bolt carrier, top roller bearings and side roller bearings, and a handguard assembly, wherein the lower receiver assembly and its AR-style fire control and magazine well are releasably attached to the upper receiver, and prior to attachment of the barrel assembly the bolt carrier group assembly, consisting of the bolt carrier, bolt head, bolt charging handle, top roller bearings, and side roller bearings is inserted unto the upper receiver. An extension of the barrel assembly is releasably attached to the upper receiver. The barrel assembly is releasably secured by releasable attachment of the handguard assembly to a barrel extension receiver of the upper receiver assembly.

Assignee: Defense Research and Development, LLC
Inventors: Swetal K. Patel
Filing date: 2024-09-23

bolt actionriflemodularfirearm

The patent describes a modular bolt action rifle system featuring roller bearings that enhance the movement of the bolt carrier within the upper receiver, allowing for a smoother operation without direct contact with the receiver’s interior. The system includes an upper receiver with a barrel assembly, a lower receiver with an AR-style fire control system, and a handguard assembly, all designed for easy assembly and disassembly.

Claim 1

1 . A modular bolt-action rifle system, comprising: an upper receiver assembly comprising a bolt and a bolt carrier group assembly; wherein the bolt carrier group assembly comprises: a bolt head, a bolt carrier, side roller bearings fastened to each of side of the bolt carrier; top roller bearings fastened to the top of the bolt carrier; and a bolt charging handle, a lower receiver assembly comprising: a fire control system; and a magazine well; a barrel assembly; and a handguard assembly; and wherein the load of the bolt carrier within the upper receiver is supported by the side roller bearings, and the bolt carrier moves within the upper receiver along a longitudinal axis of the rifle guided by the side and top roller bearings and without contact by the bolt carrier with the interior of the upper receiver. an upper receiver assembly comprising a bolt and a bolt carrier group assembly; wherein the bolt carrier group assembly comprises: a bolt head, a bolt carrier, side roller bearings fastened to each of side of the bolt carrier; top roller bearings fastened to the top of the bolt carrier; and a bolt charging handle, a lower receiver assembly comprising: a fire control system; and a magazine well; a barrel assembly; and a handguard assembly; and wherein the load of the bolt carrier within the upper receiver is supported by the side roller bearings, and the bolt carrier moves within the upper receiver along a longitudinal axis of the rifle guided by the side and top roller bearings and without contact by the bolt carrier with the interior of the upper receiver.

Google Patents

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USPTO PDF

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/12504244