One Horse Medium .300 BLK 1:7 Pistol-Length - AR-15 Barrel - 7.5"

As compact as .300 Blackout gets in an AR platform. The One Horse 7.5-inch .300 BLK barrel delivers pistol-length gas, black nitride finish, and mil-spec 4150 construction in the shortest practical barrel length for the cartridge — built for ultra-compact SBR builds, suppressed pistol configurations, and any application where size and suppressor compatibility are the primary design goals.

The One Horse .300 BLK 7.5-inch Barrel is a compact AR-15 barrel chambered in .300 Blackout, machined from 4150 steel with a black nitride finish and medium profile on a pistol-length gas system, designed for ultra-compact SBR and pistol builds running suppressed subsonic and supersonic .300 BLK ammunition.

Three features define this barrel's suitability for compact and suppressed .300 BLK builds. The pistol-length gas system is tuned for reliable cycling in a 7.5-inch .300 BLK barrel, providing the correct dwell time for the cartridge at this length to cycle both supersonic and subsonic loads consistently with or without a suppressor. The 1:7 twist rate handles the full range of .300 BLK projectile weights reliably, including the 200-to-240-grain subsonic loads that are the primary reason for building a suppressed .300 BLK platform in the first place. Black nitride finish protects the bore from accelerated carbon fouling common in suppressed configurations, extending the cleaning interval and maintaining consistent performance over a high round count.

Compatible with mil-spec AR-15 upper receivers and pistol-length gas systems. 5/8x24 threaded muzzle for direct-thread suppressor attachment.

4150 steel. Black nitride finish. Medium profile. Made in the USA.

The definitive barrel choice for ultra-compact suppressed .300 BLK SBR and pistol builds, home defense configurations, and any application requiring maximum maneuverability in a .300 Blackout platform.

By One Horse. Made in the USA. Standard manufacturer warranty applies.