A camshaft; the element of a typical motor that is timed using the crankshaft to actuate the valves. Some wood formed like stock of a rifle, with a horizontal club projecting from 1 part. It magically turns semi-automatic tools (those that fire one round per pull regarding the trigger) into bullet-hoses; a device which uses the recoil of a gun to fire another round.One of many how to switch your shitty california-legal semi-automatic AR-15 into a machine-gun. Quite popular in US says in which semi-automatic rifles are legal; chiefly utilized by man-children and 13-year-old males. From the down-side, it really impedes precision, and so is worthless for crooks.