One Horse Complete Upper | .300 BLK | 10.5″

This One Horse complete AR-15 upper is a compact .300 Blackout assembly built around a 10.5″ medium-contour barrel. It ships with a nitride-finished bolt carrier group and a charging handle, and includes a 10″ M-LOK handguard for modular accessory mounting. The barrel uses a 1:7 twist and a pistol-length gas system suitable for short-barrel and suppressed configurations. The unit is finished in matte black and is designed to mate with Mil-Spec AR-15 lower receivers.

Product Specifications

• The caliber is .300 BLK.
• The barrel measures 10.5 inches.
• The barrel contour/profile is Medium.
• The twist rate is 1:7.
• The gas system is Pistol.
• The muzzle thread is 5/8×24.
• The handguard length is 10 inches.
• The bolt carrier group finish is nitride-finished.
• The package includes a charging handle.
• The upper is compatible with AR-15 Mil-Spec lowers.
• The barrel material is 4150 steel.
• The finish is Matte.
• The color is Black.
• The country of origin is U.S.A..
• UPC: 850078799326.

This upper is well-suited for compact AR pistol builds and applications relying on suppressed or subsonic loads. With a 10.5″ medium contour barrel, a 1:7 twist rate, and a nitride-finished BCG, it provides a straightforward, ready-to-install solution for short-barrel .300 BLK configurations. The 10″ M-LOK handguard keeps weight down while offering modularity for lights, grips, or other accessories.