The 76-mm regimental gun M1943 (OB-25) (Russian: 76-мм полковая пушка обр. 1943 г. (ОБ-25)) was a Soviet infantry support gun developed in 1943 by M. Yu. Tsiryulnikov at the ordnance plant in Motovilikha. The gun used a modernized barrel from the 76 mm regimental gun M1927 and the carriage from the 45 mm anti-tank gun M1942 (M-42). The gun was intended for destruction of light field fortifications and openly placed personnel by direct fire. HEAT shells gave it limited anti-armor capabilities. 76.2-mm regimental guns M1943 completely replaced M1927 guns in production that year and were built until the end of the German-Soviet War. Soon after the end of the war the production ceased due to insufficient range and muzzle velocity.