Second highlight 75/55-millimetrovoy RAK.41 was carrying a shield that changed the lower carriage — also found application.
In the design bureau plant number 172 (not to be confused with the OKB-172) in a 44-year projected 76-mm regimental gun M-3-1, which was implemented in the scheme 75/55-millimetrovoy RAK.41. In November 1944, began proving ground tests most experienced M-3-1. In 1945, on the basis of M-3-1 made 45-mm anti-tank gun M-5. The plant, the index was given an anti-gun either through ignorance of its own design office work, or in order to confuse "unsleeping enemy." The index of M-5 in 1930. had a 122-millimeter mortar regiment, and in the 44-year tested 122-mm cabinet gun, also received the designation M-5. Obviously, both of the guns were made by the number 172.
But back to the 45-mm anti-tank gun. Its trunk was commonplace, such as tenderloin, as of old times and the 45-millimeter anti-tank guns, with the same 16 rifling. Automatic vertical wedge gate. On the carrier board had established the main part of the anti-tank weapon: the top machine with a gun and pointing mechanisms, sliding frame, torsion cushioning with axes and motorcycle disc wheels, tires having 3.75 g 19. The top machine, representing a spherical mask was mounted in a panel with vertical pins. Rotary and lifting mechanisms helical. The angle of the horizontal guidance was 55 °. and the angle of the vertical guidance from -9 ° to +25 °. Recuperator spring, hydraulic recoil brake, limit recoil length was 750 mm. The height of 570 mm strip of fire. Shield shielded, consisted of a pair of sheets of different thicknesses: wheel — 4 mm rear — 3 mm. Weight system in the firing position was 493 kg.
Ammunition and Ballistics gun M-5 is one hundred percent coincided with the M-42 (weight 1430 g of an armor-piercing projectile, the initial speed of 870 meters per second, etc.).
The design of 45-mm anti-tank gun M-5 had several advantages over the anti-tank guns have a "classic" in respect of carriage of the device simplicity and greater compactness, greater adaptability in production and gain in weight. All the same, the weight of the gun was pretty big for a battalion guns. Because of the low altitude axis of the tool and a longish trunk with sleigh on uneven terrain utykaniya occurred in the ground. Growth armor tanks South American production on the one hand, and the development of recoilless rifles and rocket-propelled grenades Russian on the other deprived 45 — millimeter antitank guns prospects. M-5 for service was not accepted.