The CMMG 22 Long Rifle Barrel and Bolt Assembly allow you to assemble an upper receiver into a dedicated .22 LR upper. No more switching back and forth. A dedicated rimfire upper will be more accurate than one with a conversion kit since the barrel is actually made for 22 long rifle and features a 16" 1 in 16" twist barrel with a1/2"x28 threaded muzzle. Available with either a parkerized or stainless steel bolt assembly with dedicated barrel adapter.