122 mm corps gun M1931 (A-19) (122-мм корпусная пушка обр. 1931 г. (А-19)) was a Soviet field gun, developed in late 1920s and early 1930s. In 1939 the gun was replaced in production by an improved variant, M1931/37. The piece saw action in World War II with the Red Army. Captured guns were employed by Wehrmacht and the Finnish Army.
On 17 June 1929 a prototype piece, along with technological documentation, was ordered from Motovilikha Plants. The piece underwent trials starting in October 1931, with two barrels of different construction, both fitted with muzzle brake. In May 1932 the gun was sent for improvements to the No 38 Plant, where it received designation A-19. In 1933 three more prototypes were ordered from the Barrikady Plant in Stalingrad and were completed in March 1935. The gun reached trials again in November 1935. After successfully completing the trials, it was adopted by RKKA on 13 March 1936 as 122 mm corps gun M1931 (A-19).
|Production of M1931, pcs.|
|Produced, pcs.||30||91||78||150||256 (including M1931/37)|
The barrel consisted of liner, jacket and screwed-upon breech. Early production barrels hade built-up construction, but in 1936 these were replaced in production by free liner barrels. The breechblock was of interrupted screw type, similar in construction to that of the 152 mm howitzer M1910/37. Unlike early prototypes, productional barrels did not have muzzle brake. Recoil system consisted of hydraulic recoil buffer and hydropneumatic recuperator, both located inside the cradle under the barrel.
The limber of the experimental 152 mm ML-15 was used.
Initially a separate transportation (with the barrel removed from the carriage and transported on a special wagon) was considered. However, following the trials it was decided to always tow the gun as a single piece. Several types of artillery tractors were employed: S-2 Stalinets-2, Komintern and, from 1943, Ya-12.
Soon after the outbreak of the Great Patriotic War the corps artillery was eliminated (as rifle corps themselves were eliminated) and was only reintroduced late in the war. Those new artillery regiments were issued 122 mm guns along with other pieces, mainly 107 mm guns and 152 mm howitzers, in total 16-20 pieces per regiment. On 1 June 1944, RKKA corps artillery possessed 387 A-19s (along with some 750 107 mm and 152 mm pieces), an on 1 May 1945 - 289 A-19s (again along with some 750 100 mm, 107 mm and 152 mm pieces).
The gun was also used by artillery units of the Reserve of the Main Command (RVGK). In mid-1941 a cannon regiment of the RVGK had 48 A-19; in autumn 1941 these regiments were reorganized, a new, smaller, regiment had 18 A-19s. From 1942 cannon brigades were introduced, with 36 A-19s each. Such brigade could be a part of an artillery division - a huge formation, with up to four brigades of A-19 or ML-20 (meaning up to 144 pieces).
By June 1941 the RKKA possessed, according to different sources, 1257 (1236 in the Army and 21 in the Navy) or 1300 A-19s. The gun proceeded to be used throughout the Great Patriotic War.
The A-19 was primarily used for indirect fire against enemy personnel, fortifications and key objects in the near rear. It was also equipped with armour-piercing shells for direct fire against armoured targets. Although not an ideal anti-tank gun because of its large size, slow traverse and relatively slow rate of fire, in 1943 the A-19 was one of a few guns effective against new German tanks.
The Finnish Army captured 25 pieces in 1941 and also pressed them into service. The same designation 122 K/31 was applied to both variants. Because of shortage in heavy tractors, the gun was mostly used in coastal artillery. Four pieces were lost; the rest remained in service after the war. In 1980s some pieces had their barrels replaced with 152 mm barrels of ML-20; the resulting pieces were designated 152 H 37-31. In late 1980s both 152 H 37-31 and the remaining 122 K/31 received new 152 mm L/32 barrels manufactured by Vammas, to become 152 H 88-31. Only in 2007 the Finnish Army began to remove these guns from service.
As mentioned above, late production M1931s differed from early production ones. Guns manufactured starting in 1936 had free liner barrel construction in contrast to the earlier built-up barrels; in 1937 changes in breech block construction were introduced, and some late production pieces received ML-20-type wheels with pneumatic tires.
In addition, the M1931 had a number of experimental variants.
In 1933, development of a carriage with improved off-road mobility was started. The carriage in two variants - on tracks and on large, tractor-type wheels - reached trials in 1937 and was found to be not durable enough.
In 1933-36 the gun was involved in experiments with pre-rifled projectiles. For these experiments a special variant of the barrel was produced. The experiments were stopped because of inherent deficients of those projectiles, namely more complicated loading process and lower accuracy.
Another variant, with bag loading, designated Br-3, reached trials in 1937, but was not adopted.
The carriage of M1931, almost unmodified, was used for the 152 mm gun M1910/34.
As already mentioned, in Finland carriages of the A-19 were fitted with 152 mm barrels, resulting in two models:
The carriage of M1931 had a number of shortcomings though. The elevation mechanism was slow and unreliable; solid-tired wheels hindered mobility to some extent; there were technological problems in carriage production. These shortcomings eventually led to adopting a better carriage, creating the M1931/37.
As calibers similar to 122 mm were not typical for western field artillery of World War II era, pieces directly comparable to the M1931 were rare.
The German 10.5 cm sK 18 was significantly lighter (5.64 t) while having about the same range (19 km), but fired much smaller 15 kg shell; on the other side, the 15 cm K 18 was heavy (combat weight 12.46 t), limited production (101 pieces) weapon, more comparable to the Soviet 152 mm Br-2. Late in the war Germans worked on a number of 128 mm field guns; one of these designs, the 12.8 cm K 81/2, was a gun with combat weight of 8.2 t, based on a heavily modified carriage of captured 152 mm ML-20. However, little is known about its characteristics; anyway, none of these 128 mm designs reached mass production.
British Army and U.S. Army both employed 4.5 inch (114 mm) pieces with similar characteristics, and designed to utilize the same ammunition - BL 4.5 inch Medium Field Gun and 4.5 inch Gun M1 respectively. The 5.65-ton M1 fired a 24.9 kg shell to the maximum range of 19.3 km; however the only type of ammunition available for the gun was a HE-frag shell, and that contained only about two kg of explosives.
|Type||Model||Projectile weight, kg||HE weight, kg||Muzzle velocity, m/s||Range, m|
|Armor piercing shells|
|АРНЕВС (from early 1945)||BR-471B||25.0||800||4,000|
|High explosive and fragmentation shells|
|HE-Fragmentation, howitzer||OF-462||21.7||3.67||765 (charge no. 1)||16,600|
|Chemical, howitzer||H-462||21.8||705 (charge no. 2)||19,800|
|Armour penetration table|
|АРНЕВС shell BR-471B|
|Distance, m||Meet angle 60°, mm||Meet angle 90°, mm|
|APHE shell BR-471|
|Distance, m||Meet angle 60°, mm||Meet angle 60°, mm|
|Different methods of armor penetration measurement were used in different countries / periods. Therefore, direct comparison is often impossible.|
The M1931 can be seen: