Abstract: A firearm barrel accessory that quick connects and disconnects to a firearm barrel by rotating is described. The accessory may be a firearm suppressor with a silencer barrel, a mount retention ring located inside the silencer barrel that includes longitudinal grooves that lead to circumferential grooves that have a first radial side and a second radial side. The firearm barrel is attached to a muzzle break that may include a plurality of lugs that fit into longitudinal grooves. After placement in the longitudinal grooves, the silencer barrel and mount retention ring are rotated/twisted about the silencer barrel longitudinal axis so that the circumferential grooves move relative to the lugs until the lugs contact the second radial side, at which point the mount retention ring ceases to rotate while the silencer barrel continues to rotate. A ratchet retention ring may exert tension on the mount retention ring in the rearward direction.