Note: This barreled upper receiver assembly has a barrel length under 16” and is therefore subject to all NFA rules and regulations. Know your local laws before purchasing.
This upper receiver assembly comes complete with a 10” .300 Blackout barrel and a pistol length gas system. The forged 7075-T6 aluminum receiver features a billet design and looks great when paired with the M4E1 lower receiver. The ATLAS R-ONE free float handguard is made from the same material with the same hardcoat anodized finish and features a lightened profile with M-LOK slots for accessories. This .300 BLK AR-15 barreled upper receiver assembly does not include a BCG or charging handle but does include the forward assist and dust cover. Build a high quality .300 BLK AR pistol today with the M4E1 upper receiver assembly.