Converting a 5.56/.223-chambered AR-15 to a PCC (pistol caliber carbine) in 9mm isn't difficult. Brownells Gun Tech™ extraordinaire Steve Ostrem gives us an overview of the necessary mods. First, the barrel: "AR-9" barrels have no locking lugs and no gas port because these guns are blowback operated. As a result, they use a heavier bolt / carrier assembly to help keep the breech closed (no gas key, either). A heavier 9mm buffer is also needed, but the good news is it'll work with a standard carbine spring. You'll need a new muzzle device, too, with an exit hole big enough for a 9mm (.355") bullet. Last but not least, you'll need a magazine well conversion unit, such as those from American Tactical, Hahn Precision and Stern Defense, because AR-9s use Colt SMG, Glock® or other pistol mags that are too small for the 5.56 magwell opening. Assemble it all like any other AR-15, do a check for headspace, and hit the range!
Learn more: [ Ссылка ]
