If you’re looking for a top-of-the-line AR-15 upper receiver group, you can’t go wrong with the BCM Standard 300 BLK AR-15 Upper Receiver Group. This professional grade weapon is built around a 41V50 chrome moly vanadium steel barrel that is MIL-SPEC approved and guaranteed to outlast most commercial materials on the market. Additionally, the BCM MCMR Handguards are constructed from 100% aluminum and hardcoat anodized for an anti-reflective, corrosion resistant finish. M-LOK mounting slots on seven sides provide ample space for all your favorite accessories, plus there’s a continuous Picatinny rail for even more customization options.
NOTE: Does not include a bolt carrier group or charging handle.
Notice from the manufacturer:
“BCM has taken great care to ensure the best possible performance and interchangeability. However, due to the large operational range of 300 Blackout ammunition in the market place, BCM cannot guarantee function will all ammunition types in all conditions. These barrels were designed to run with a carbine buffer with subsonic ammo and a H3 buffer with high velocity ammo. Fine tuning may be required in limited instances based on ammo and buffer choices that work best for the desired application. BCM also recommends running the Crane O-ring (provided with all BCM Bolt Carrier Groups) over the extractor with 300 Blackout.”