(b) The distance traveled by a projectile from the firearm to the target. RECEIVER The basic unit of a firearm to which the barrel and other components are attached. Since the Gun Control Act of 1968, all receivers must be serial numbered. RECOIL: The backward movement of a gun when fired, caused by the pressure of the propellant gas.
PROCEDURES FOR CALIBER .50 MACHINE GUN : 1. GENERAL DATA. Tests have been conducted to determine the number of rounds which can be fired in the caliber . 50 gun without causing a cook-off. It has been determined that 150 rounds can be fired from an aircraft barrel and 300 from an antiaircraft barrel without reaching cook-off conditions.