76-mm divisional gun M1939 (F-22 USV or USV) (Russian: 76-мм дивизионная пушка обр. 1939 г. (Ф-22 УСВ or УСВ)) was Soviet 76.2-mm divisional gun, adopted for the Red Army service in 1939 and utilized in Great Patriotic War. The gun was intermediate model between semi-universal divisional gun F-22 and improved and numerous ZiS-3 which eventually replaced it in production and service.
In 1937, unsatisfied with both the obsolete 76-mm divisional gun M1902/30 and the new, but flawed 76-mm divisional gun model 1936 (F-22), the RKKA command initiated development of a new gun. The requirements, issued in March that year, specified elevation of 45° and combat weight of no more than 1,500 kg. The gun was supposed to have the same ballistics as the M1902/30 and use the same ammunition.
Three design bureaus joined the program - Kirovskiy Plant bureau under I. A. Makhanov, No. 92 Plant bureau under V. G. Grabin, and AKB-43 (KB AU) under M. N. Kondakov. The L-12 of Kirovskiy Plant was the first to reach ground tests (in April-May 1938), was returned for revision, tested again in August and given to the RKKA for further trials. Grabin's gun went through ground tests in March-April 1939 and was also given to the army. Although its designation - F-22 USV or simply USV - suggested that the gun was only an upgrade of the F-22, in fact it was a completely new design. The third competing project, OKB-43's NDP, failed ground tests in April 1939. RKKA tested the remaining designs from 5 June to 3 July 1939 and was generally satisfied with both of them. The USV was found to have less "childhood diseases" and was therefore recommended for production.
The USV entered production in 1939; 140 pieces were built until the end of the year and 1,010 more in 1940. In 1941 the production was stopped as the plan for divisional guns was already fulfilled. Moreover, RKKA considered transition to larger caliber divisional guns, such as the 107-mm gun model 1940 (M-60). With the beginning of Great Patriotic War the production was reopened at No. 92 and Barrikady plant in Stalingrad; it amounted for 2,616 pieces in 1941 and 6,046 in 1942. From late summer of 1941 the gun was being gradually replaced in production by yet another Grabin's design - ZiS-3 - and by the end of 1942 the process was completed.
guard rifle divisions from December 1942 had three artillery battalions (two batteries of 76 mm guns and one battery of 122 mm howitzers each), totaling 24 76-mm guns. From December 1944 they were reorganized to have an artillery brigade of three regiments, including light regiment with 20 76-mm guns. From June 1945 rifle divisions were reorganized identically.
Motorized divisions had two mixed battalions (battery of 76 mm guns, two batteries of 122 mm howitzers), totaling 8 76-mm guns. Cavalry divisions until August 1941 also had 8 76-mm guns, then their divisional artillery was removed and in summer of 1942 restored again.
Rifle brigades from 1939 had 8 76-mm divisional guns, motorized and mechanized brigades - 12.
Cavalry corps from late 1942 had artillery battalion of 12 pieces. Tank and artillery corps in late 1944 received light artillery regiment with 76-mm guns (24 pieces).
The USV was also used by artillery units of Reserve of the Main Command, namely: anti-tank artillery brigades (24 pieces, from 1942 - tank destroyer brigades with 16 pieces), by light artillery brigades (60-72 pieces) and by breakthrough artillery divisions (light brigade with 72 pieces, from 1944 - with 48 pieces).
By 1 June 1941 RKKA possessed 1,070 USVs. Many were lost in combat, but some remained in service until the end of Great Patriotic War. It's not clear whether the gun saw combat in the earlier Winter War.
In 1941-42 Wehrmacht captured hundreds of USVs and adopted them as field guns, designated 7.62 cm F.K.297(r). By March 1944 359 pieces were in service, including 295 in the West, 40 in Denmark and 24 in the East.
Some USVs in German service were converted to anti-tank guns, designated 7.62 cm PaK 39(r). The modification included rechambering for bigger cartridge, muzzle brake, elevation controls were moved to the left side of the barrel where the sights resided. All those guns were of pre-war production bunch, as guns produced during the war had weaker breech part. The exact number of converted pieces is unknown, according to some sources there were up to 300. Anti-tank performance is also hard to determine. During trials held in 1943 a projectile from a captured gun penetrated the front armor of the KV tank (75 mm at 60°) from 600 m.
The Finns captured 9 units, but never took them into active service. Known as 76 K 39.
|Type||Model||Weight, kg||HE weight, g||Muzzle velocity, m/s||Range, m|
|Subcaliber (from April 1943)||BR-354P||3,02||-||950||500|
|HEAT, steely iron (from May 1943)||BP-350A||5,28||623||355||500|
|High explosive and fragmentation shells|
|Fragmentation, steely iron||O-350A||6,21||540||680||10,000|
|HE-Fragmentation, limited production||OF-363||7,1|
|HE, steel, old Russian||F-354||6,41||785||640||9,170|
|HE, steel, old Russian||F-354M||6,1||815|
|HE, steel, old french||F-354F||6,41||785||640||9,170|
|Shrapnel with 22 sec / D tube||Sh-354||6,5||85 (260 bullets)||624||6,000|
|Shrapnel with T-6 tube||Sh-354T||6,66||85 (250 bullets)||618||8,600|
|Canister shot||Sh-350||549 bullets||200|
|Smoke, steel||D-350||6,45||80 TNT + 505 yellow phosphorus|
|Smoke, steely iron||D-350A||6,45||66 TNT + 380 yellow phosphorus|
|Incendiary||Z-354 (project 3890)||6,5 (6,66)||240||624||6,200|
|Armour penetration table|
|AP Projectile BR-350A|
|Distance, m||Meet angle 60°, mm||Meet angle 90°, mm|
|Subcaliber projectile BR-354P|
|Distance, m||Meet angle 60°, mm||Meet angle 90°, mm|
| These data was obtained by Soviet methodics of armour penetration measurement (penetration probability equals 75%). |
They are not directly comparable with western data of similar type