Very early Snipers had a "button" style knob on the cocking rod, so that you could "degas" the gun. When the 12-gram was running low, or you had partially unscrewed the tank (or shut off the Thermo tank) rather than cocking and firing the gun, you could thump the 'button' with your palm, which would vent everything through the valve.
Doc.
Doc.
Comment