107 mm divisional gun M1940 (M-60)

107 mm divisional gun M1940 (M-60)
M-60 at the Artillery Museum, Saint Petersburg
Type	field gun
Place of origin	USSR
Service history
Used by	USSR
Wars	WWII
Production history
Designer	No. 172 Plant, F. F. Petrov
Designed	1938-1940
Manufacturer	No. 172 Plant, No. 352 Plant
Produced	1940-1941
No. built	139
Specifications
Weight	Combat: 4,000 kg (8,818 lbs) Travel: 4,300 kg (9,480 lbs)
Length	8.09 m (26 ft 7 in)
Barrel length	Bore: 4.47 m (14 ft 8 in) L/41.8 Overall: 4.6 m (15 ft 1 in) L/43
Width	2.20 m (7 ft 3 in)
Height	1.92 m (6 ft 4 in)
Crew	8
Caliber	106.7 mm (4.21 in)
Breech	interrupted screw
Carriage	split trail
Elevation	-4.5° to 45°
Traverse	60°
Rate of fire	6-7 rounds per minute

The 107 mm divisional gun M1940 (M-60) (Russian: 107-мм дивизионная пушка образца 1940 года (М-60)) was a Soviet artillery piece, developed in the late 1930s in order to provide Soviet divisional artillery with a powerful field and anti-tank gun. The weapon entered production in 1940, but soon after the outbreak of the German-Soviet War, production ceased; only a limited number of pieces were built. These guns saw service in the Red Army during the war.

Until the late 1930s, Soviet divisional artillery consisted of three-inch (76.2 mm) guns, designed to use the same model 1900 cartridge case, complemented by 122 mm howitzers. The reason for continued reliance on the 76 mm caliber was that the USSR had a large supply of three-inch (76 mm) ammunition, some delivered during World War I and also possessed suitable manufacturing equipment. Various improvements in metallurgy, chemistry and ordnance design allowed the production of guns such as the USV and the ZiS-3, which were superior to the older ones in many respects, being lighter and featuring modern split trail carriages. However, all these improvements could not remedy the inherent weakness of the existing high-explosive shell. The three-inch (76 mm) caliber was chosen by the Russian Imperial Army prior to the trench warfare era for its sufficient shrapnel performance; but high-explosive shells of the caliber contained a relatively small amount of explosives (typically some 600-700 grams) that were only moderately effective against field fortifications.

The decision to initiate development of larger caliber divisional guns was made in the second half of 1937. Late that year the 95 mm was proposed. On 10 March 1938 the Main Directorate of Artillery (GAU) initiated work on a 95 mm divisional gun at the Kirov Plant and the No. 92 Plant. The former quickly abandoned the development, but the UZTM Uralmash production facility swiftly joined the program. Both guns were supposed to have a companion piece in the form of the 122 mm howitzer.