CMMG Anvil Mk4 AR-15 platform chambered in .45 ACP with 16-inch barrel, using CMMG's Radial Delayed Blowback system to handle the pistol cartridge in a rifle-length build. Type: Rifle Action: Semi-Automatic Caliber: .45 ACP Capacity: 13 Year introduced: 2018, USA Weight: 96 oz Overall length: 32" Status: Active Intended use: Sporting, Home Defense, Competition