152 mm howitzer M1938 ( M - 10 ) 152 - mm howitzer M1938 ( M - 10 ) ( ) was a Soviet 152 . 4 mm ( 6 inch ) howitzer of World War II era . It was developed in 1937 - 1938 at the " Motovilikha Mechanical Plant " by a team headed by F . F . Petrov . Although production of the gun was stopped in 1941 , it saw combat with the Red Army until the end of World War II and remained in service until the 1950s . Captured pieces were used by Wehrmacht and the Finnish Army . The latter kept the M - 10 in service until 2000 . In a tank - mounted variant , M - 10T , the gun was mounted on the KV - 2 heavy tank . Development history . By early 1930s the Red Army ( RKKA ) started to look for a replacement for the 152 - mm howitzer M1909 and the 152 - mm howitzer M1910 . Those pieces , developed before World War I , had unsprung fixed trail carriages and short barrels , which meant poor mobility , insufficient elevation and traverse angles and short range . Although both pieces were eventually modernized , resulting in the 152 - mm howitzer M1909 / 30 and the 152 - mm howitzer M1910 / 37 respectively , these were relatively minor upgrades which brought only limited improvement in some areas and didn ' t address others . It was clear that a completely new design was needed . However , at that time Soviets had little experience in developing modern artillery pieces . Soviets initially tried to solve that problem through a collaboration with Germany . From its part , Germany , constrained by the limitations of the Treaty of Versailles , looked for a way to proceed with development and joint projects gave them such an opportunity . Among other weapons supplied by Germans was a heavy howitzer , designated in the USSR 152 - mm howitzer M1931 ( NG ) . Soon the " Motovilikha Mechanical Plant ( MMZ ) " was entrusted with the production of NG . However , only 8 pieces were completed in 1932 - 1934 , and then the production was stopped . The design proved to be too complicated for the Soviet industry of early 1930s ( the same fate befell some other designs , e . g . the 122 - mm howitzer M1934 or 20 - mm and 37 - mm autocannon s ) and was considered somewhat heavy ( 5 , 445 kg in travelling position ) . But these early failures it gave Soviet developers some valuable experience . In 1937 , F . F . Petrov and his design team at the " Motovilikha Ordnance Plant " started work on a new design , the M - 10 . Technical papers were submitted to the Artillery Directorate on 1 August 1937 and on 2 November the first prototype was completed . Ground trials ( 19 – 25 October 1938 ) featured two pieces : No . 302 ( L / 25 barrel with constant rifling ) and No . 303 ( L / 20 barrel with progressive rifling ) . The No . 303 was found to be superior . The trials also revealed numerous defects in the gun construction : the howitzer suffered from insufficient upper carriage strength , leaks in recoil buffer , unreliable suspension etc . For army tests early in 1939 an improved design with lengthened barrel was presented . Another series of army tests followed , from 22 December 1939 to 10 January 1940 , but even before it started - on 29 September 1939 - the gun was adopted as 152 mm divisional howitzer model 1938 . Later the word " divisional " was removed from the designation . Production history . The M - 10 entered production at the " Plant No . 172 " in 1939 . Until the end of the year 4 pieces were manufactured , 685 more in 1940 and 833 in 1941 . About 340 barrels for KV - 2 heavy tanks were also built ( for 334 serial production tanks and a few prototypes and experimental vehicles ) . Soon after the outbreak of the war mass production of the gun was stopped . The following reasons are typically cited : . Some found these arguments questionable . Later in the war corps artillery employed the 152 - mm howitzer M1943 ( D - 1 ) with the same ballistics . Production rates were growing . Even early in the war , the Red Army wasn ' t passive , but tried to attack at every opportunity ; moreover , howitzers are certainly useful in defensive combat too , e . g . for suppressing enemy howitzers . A historian M . Svirin offered the next explanation instead : Description . The M - 10 was much more advanced design compared to older Soviet 152 mm howitzers . It had modern split trail carriage , which allowed for much larger traverse . The trails were of riveted construction . The carriage was equipped with suspension and with wheels from the ZiS - 5 truck , meaning higher transportation speed . The barrel , much longer than that of older designs , was fitted with interrupted screw breechblock with recoil devices consisting of hydraulic recoil buffer and hydropneumatic recuperator . The recoil length was variable . Gun shield provided the crew with limited protection from bullets and shell fragments . Unlike its eventual successor , the D - 1 , the M - 10 was not equipped with muzzle brake . While softening a recoil and thus allowing lighter carrige , muzzle brake has a disadvantage of redirecting some of the gases that escape the barrel toward the ground where they raise dust , revealing the gun position . The gun could be towed by an artillery tractor or by a horse team . In the latter case , a 400 - kg limber was used . Organization and employment . Under the organization of 1939 , each rifle division had a howitzer regiment with a 152 - mm howitzers battalion ( 12 pieces ) . In July 1941 these regiment were cancelled . Same fate befell 152 - mm howitzers battalions of motorized and armored divisions . In 1944 , rifle corps of the Red Army had one artillery regiment each . Those regiment consisted of five batteries ( totaling 20 pieces ) , equipped with 152 - mm howitzers , 122 - mm or 107 - mm guns . Reserve of the Main Command included howitzer regiments ( 48 pieces ) and heavy howitzer brigade s ( 32 pieces ) . Those could be merged to form artillery division s . On 1 June 1941 the RKKA possessed more than thousand M - 10s . Many were lost in the early phase of the war , combined with a decision to stop the production it meant only limited quantity remained in service ; these remaining guns in dwindling numbers were used for the remainder of World War II . The M - 10 was used against personnel , fortifications and key objects in the rear . Many guns were captured by the Wehrmacht early in the war , and adopted as 15 , 2 cm sFH 443 ( r ) . The Finnish Army captured 45 pieces and further 57 were purchased from Germany in 1944 . In Finland the howitzer , designated 152 H 38 , was issued to five heavy artillery battalions and actively used in battle . Finns rather liked the gun , but considered it somewhat heavy . After the end of the hostilities , the M - 10 remained in the Finnish service ; in 1980s there were some considerations of modernizing it , but the idea was dropped ; the guns were stored in the army depots until 2000 and then they were finally retired . The surviving M - 10 howitzers can be seen in various military museums and war memorials , for example in the Museum of Artillery and Engineering Forces , Saint Petersburg , Russia , in the Brest Fortress , in the US Army Ordnance Museum , in Helsinki Military Museum and Hämeenlinna Finnish Artillery Museum . Variants . In addition to the towed howitzer , a vehicle - mounted variant was developed for use in KV - 2 heavy tanks . This variant - 152 mm tank howitzer M1938 ( M - 10T ) - had shorter barrel . A single prototype with powder bag loading was built in 1939 . Summary . The M - 10 project provided the RKKA corps artillery with a modern 152 - mm howitzer , which combined good firepower with good mobility ( although , as the example of the D - 1 shows , the latter characteristic could be improved without compromising the former ) . When compared to a typical contemporary howitzer of similar calibre , the M - 10 had shorter range , but was lighter . E . g . the German 15 cm sFH 18 had a range of 13 , 325 m - about one kilometer longer than that of the M - 10 - but also weighed much more ( 5 , 510 kg in traveling position ) . The same can be said about the US 155 - mm howitzer M1 ( 14 , 600 m , 5 , 800 kg ) or 149 - mm howitzer manufactured by the Italian Ansaldo ( 14 , 250 m , 5 , 500 kg ) . A German howitzer with characteristics similar to those of the Soviet one - the 15 cm sFH 36 - didn ' t reach mass production . Compared to older pieces such as the French Schneider model 1917 ( 11 , 200 m , 4 , 300 kg ) , the M - 10 had advantage in range and comparable weight . Ammunition . The M - 10 used separate - loading ammunition , with eight different charges . The charges ranges from the " full charge " Zh - 536 and smaller charges ranging from the " first " to " sixth " , which was the smallest . A " special charge " was used with the BP - 540 HEAT projectile . Propellant charges were produced in " full " and " third " variants in munitions factories . All other charges were derived from them by removing small gunpowder bags from charge cartridge . For flash suppression there was a special chemical mixture which was inserted into cartridges before night firing . 152 mm projectiles for the M - 10 weighed about 40 kg , making a difficult job for loaders , who had to carry the projectiles alone . When set to fragmentation mode , the OF - 530 projectile produced fragments which covered an area 70 meters wide and 30 meters deep . When set to high - explosive ( HE ) action , the exploding shell produced a crater about 3 . 5 meters in diameter and about 1 . 2 meters deep . The OF - 530 is still fired from modern 152 mm ordnance pieces of the Russian Army . The G - 530 HEAC anti - concrete shell had a muzzle velocity of 457 m / s when fired with the " first " charge . At a range of one kilometer it had 358 m / s terminal velocity and was able to punch through up to 80 centimeters of reinforced concrete before detonating a TNT charge which increased the total penetration to 114 centimeters . The G - 530 could not be fired with a " full " charge without putting the crew at risk of having the shell explode in the barrel . A special version of the shell , the G - 530Sh , was developed to allow use with the full charge . The BP - 540 HEAT projectile was not used during World War II . It had an armour penetration of 250 millimeters at an incident angle of 90° , 220 millimeters at 60° , 120 millimeters at 30° .