Browning Machine Gun, Caliber .30 inch, HB, M1919A4, Ground. FM 23-45 Browning Machine Gun Caliber.30 inch, HB. M1919A4. Mounted in Combat Vehicles. FM 23-50 - USA Basic Field Manual, FM 23-50 Browning Machineguns Caliber .30 inch, M1917A1, M1919A4, M1919A4E1, M1919A6, and M37. FM 23-55 Browning machine Gun, Caliber.50 inch. HB. M2. FM 23-65 37 mm. Gun Antitank M3. FM 23-70 57 mm. Rifle M18. FM 23-80 60 mm. Mortar M2. FM 23-85 60 mm. Mortar M19. FM 23-85 81 mm. Mortar M1. FM 23-90 Chemical Mortar 4.2 inch. FM 23-92 Signal Communication. FM 24-5 Signal Orders Records and Reports. FM 24-16