Ordnance provision system. [Ordnance catalog (ordnance provision system): Groups A-T. F-237. Tabled grapical firing, M2, M3, M4, M5, M, M7, M8, M9, M10, M12, M13, M14, M15, M16, M17, M18, M19, and M20, addendum, Changes 1; Sept. 27, 1943.