Equipment scales : For guns, machine, Bren .303-inch, Mks. I and II : issued by technical scale and S.R. section, M.G.O. branch, G.H.Q (I) Army extension courses. Special text : Machine guns / prep. under the dir. of the Chief of Cavalry for use with the Extension Course of … field manual Antiaircraft artillery : markmanship and service of the piece : antiaircraft machine gun / prepared under direction of the chief of coast artillery field manual Browning machine gun caliber .30, HB, M1919A4 (mounted in combat vehicles) / prep. under dir. of the Chief of Infantry field manual Browning machine gun, caliber .30, M1917 description of the sub-target gun machine
