Ordnance provision system. Ordnance catalog (ordnance provision system): Group C, Gun, 75-mm, M1897A4, and mount, gun, M3, major items, maintenance parts and equipment required for maintenance of gun, 75-mm, M1897A4, mechanism, recoil, M1897A5, and mount, gun, M3, addendum; Dec. 21, 1912.