The Bear Creek Arsenal .300 Blackout Complete Upper (part no. UAF1396300PHB105) is a ready-to-run AR-pattern upper assembly chambered in .300 Blackout, built around a 10-inch barrel and a pistol-length gas system for a compact, maneuverable build. Bear Creek Arsenal fits the upper with an M-LOK handguard for mounting lights, optics, and other accessories directly to the rail. The 1:7 twist rate stabilizes the full range of .300 Blackout bullet weights, from lightweight supersonic loads to heavy subsonic rounds.

Key Specifications

• Chambered in .300 Blackout.
• Barrel measures 10 inches.
• Rifling uses a 1:7 twist rate, stabilizing both supersonic and subsonic loads.
• Gas system is pistol-length for reliable cycling on a short barrel.
• Handguard uses the M-LOK accessory mounting system.
• Sold as a complete upper, ready to mate to a compatible lower.

Frequently Asked Questions

What gas system does this upper use? A pistol-length gas system, matched to the 10-inch barrel.

Does this upper stabilize subsonic .300 Blackout loads? Yes, the 1:7 twist rate handles both supersonic and heavy subsonic bullet weights.

What accessory rail system does it use? M-LOK, for mounting lights, optics, and other accessories.

Buy the Bear Creek Arsenal .300 Blackout Complete Upper 10-inch Pistol Length M-LOK

Order this Bear Creek Arsenal upper from our Bear Creek Arsenal lineup of AR15 uppers for fast, insured shipping to your FFL from our Lubbock, Texas gun shop.