122 mm corps gun M1931/37 (A-19) was a Soviet field gun developed in late 1930s by combining the barrel of the 122 mm gun M1931 (A-19) and the carriage of the 152 mm howitzer-gun M1937 (ML-20). The gun was in production from 1939 until 1946. It saw action in World War II (primarily with corps and RVGK artillery of the Red Army) and remained in service for a long time after the end of the war. In addition to the towed variant, the gun had a number of vehicle-mounted derivatives.