The original BSD manuals (Base Shop Data) for the Browning caliber .30, caliber .50 machine guns and .30 caliber BAR were originally compiled by the United State’s Ordnance Department for the purpose of training U.S. Ordnance armorers how to disassemble, overhaul and reassemble these weapons. The World War II BSD’s were well illustrated with clear line drawings and written description. These rare BSDs have been digitally restored and reformatted for presentation in this manual. Today’s enthusiast will find this manual invaluable for maintaining or repairing Browning firearms.