Jan 20, 2026

US12529533 - System for delayed blow-back action firearm

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Provided is a blow-back bolt and recoil spring/buffer system for an autoloading firearm action. The blow-back bolt includes a bolt body and an actuator that is longitudinally movable relative to the bolt body to a limited extent by manual cycling. The recoil spring/buffer system has a longitudinal guide rod with at least one recess, a release component and a forward abutment slidably arranged together on the guide rod, a recoil spring is configured to bias the release component forwardly, and at least one roller body is arranged between the release component and the forward abutment. When the roller body is engaged in the recess, the release component and forward abutment are longitudinally slidably detained relative to the guide rod. Rearward movement of the actuator by manual cycling engages and displaces the release component such that the roller disengages from the guide rod recess to allow undetained rearward sliding movement against the recoil spring.

Inventors: Bryan Zeman

blow-backfirearmrecoilautoloader

The patent describes a blow-back bolt and recoil spring/buffer system designed for autoloading firearms, featuring a movable actuator and a guide rod with a recess that allows for controlled rearward movement. This system enables manual cycling to disengage a roller body from the guide rod, facilitating the operation of the firearm’s action.

Claim 1

1 . A blow-back bolt and recoil spring/buffer system for an autoloading firearm action, comprising: a blow-back bolt having a bolt body and an actuator, the actuator being longitudinally movable relative to the bolt body to a limited extent by manual cycling; and a recoil spring/buffer system comprising: a longitudinal guide rod having at least one recess; a release component and a forward abutment slidably arranged together on the guide rod; a recoil spring on the guide rod configured to bias the release component forwardly; and at least one roller body arranged between the release component and the forward abutment such that when the roller body is engaged in the guide rod recess, the release component and forward abutment are longitudinally slidably detained relative to the guide rod, wherein rearward sliding movement of the actuator by manual cycling causes displacement of the release component relative to the forward abutment such that the at least one roller disengages from the guide rod recess to allow undetained rearward sliding movement of the release component and forward abutment against the recoil spring. a blow-back bolt having a bolt body and an actuator, the actuator being longitudinally movable relative to the bolt body to a limited extent by manual cycling; and a recoil spring/buffer system comprising: a longitudinal guide rod having at least one recess; a release component and a forward abutment slidably arranged together on the guide rod; a recoil spring on the guide rod configured to bias the release component forwardly; and at least one roller body arranged between the release component and the forward abutment such that when the roller body is engaged in the guide rod recess, the release component and forward abutment are longitudinally slidably detained relative to the guide rod, wherein rearward sliding movement of the actuator by manual cycling causes displacement of the release component relative to the forward abutment such that the at least one roller disengages from the guide rod recess to allow undetained rearward sliding movement of the release component and forward abutment against the recoil spring.

Google Patents

https://patents.google.com/patent/US12529533

USPTO PDF

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/12529533