The Dead Foot Arms MCSBS in .300 BLK uses the same folding receiver system as the 5.56x45mm version with a shorter 8-inch barrel optimized for subsonic .300 BLK suppressed shooting. When folded it is one of the most compact suppressor-host AR-pistols available. Type: Pistol Action: Direct Impingement Caliber: .300 BLK Capacity: 30 Year introduced: 2019, USA Weight: 6.4 oz Overall length: 18" Status: Active Intended use: Home Defense, Suppressor Host, Military