Features:

• 300 Blackout Upper Receivers for AR15, M4, M15, and the HK-416 platform
• Available with a 9”, 12.5" or 16” Nitrided 1:8 Twist 4150 CMV steel Barrel
• M4 feedramps
• Includes AAC 51-tooth Blackout Flash Suppressor attached to 5/8-24 threads
• Knight’s Armament free-floating URX (URX II on 12.5" and 16”, URX III on 9”)
• M16 Bolt Carrier Group
• Bolt is Carpenter 158 steel and includes improved extractor o-ring
• Internally chrome lined bolt carrier
• Heat-treated gas-key with proper staking
• Full auto chamber dimensions
• Pistol length gas system on 9” Upper
• Carbine length gas system on 12.5" and 16” Uppers
• 12.5" and 16” Upper receiver includes URX with built in front sight
• Charging handle included

Benefits:

• 300 Blackout AAC Upper Receivers are designed from the ground up to function with 300 Blackout Subsonic and Supersonic ammunition
• 51T Blackout Flash Hider allows for the attachment of the recommended 762-SDN-6 sound suppressor
• Nitrided barrel, bore, and chamber provide extreme corrosion resistance and high hardness for a long life, outperforming chrome-lined barrels for longevity without the potential impediments to accuracy
• M16 Bolt Carrier Group allows these Upper Receivers to properly function on a wide variety of lowers, including semi and full-auto lowers
• URX Handguards free float the nitride barrel and allow for the attachment of a variety of accessories
• Full auto chambering enhances feeding and extraction compared to a match chamber