Self-propelled artillery was an important component of the Red Army's armored weapons system during the confrontation between the USSR and Nazi Germany and its satellites. As you know, part of the Red Army received heavy (SU-152, ISU-152, ISU-122), medium (SU-122, SU-85, SU-100) and light (SU-76, SU-76M) self-propelled artillery mounts … The process of creating the latter was launched on March 3, 1942, after the formation of a special self-propelled artillery bureau. It was formed on the basis of the 2nd department of the People's Commissariat of the Tank Industry, the head of which, S. A.
Apparently, by the spring of 1942, Ginzburg managed to get through to the leadership of the NKTP. The special bureau was instructed to design a single chassis for the ACS using automotive units and components of the T-60 tank. On the basis of this chassis, it was supposed to create a 76-mm self-propelled infantry support gun and a 37-mm self-propelled anti-aircraft gun. In May-June 1942, prototypes of the assault and anti-aircraft self-propelled guns were manufactured by plant number 37 NKTP and entered for testing. Both vehicles had the same chassis, in which there were units of the T-60 and T-70 tanks. The tests were generally successful, and therefore in June 1942 the State Defense Committee issued an order for the earliest possible fine-tuning of the machines and the release of the first serial batch for military trials. However, the large-scale battles that unfolded soon on the southern flank of the Soviet-German front demanded that the NKTP enterprises increase the production of tanks and curtailed work on self-propelled guns.
They returned to the development of installations in the fall of 1942. On October 19, the State Defense Committee decided to prepare the serial production of assault and anti-aircraft artillery self-propelled guns with a caliber of 37 to 152 mm. The executors for the assault self-propelled guns were the plant number 38 named after. Kuibyshev (Kirov city) and GAZ. The deadlines for completing the assignments were tough - by December 1, 1942, it was required to report to the State Defense Committee on the results of tests of new combat vehicles.
GOVERNANCE PAID BY BLOOD
In November, the SU-12 (plant number 38) and GAZ-71 (Gorky Automobile Plant) assault self-propelled guns were tested. The layout of the vehicles generally corresponded to the proposal of the NKTP special bureau, formulated in the summer of 1942: two parallel twin engines in the front of the self-propelled gun and a fighting compartment in the stern. However, there were also some nuances. So, on the SU-12, the motors were on the sides of the car, and the driver was placed between them. On the GAZ-71, the power plant was shifted to the starboard side, putting the driver closer to the left. In addition, the Gorky residents placed the drive wheels at the back, dragging a long propeller shaft to them through the entire car, which significantly reduced the reliability of the transmission. The result of this decision was not long in coming: on November 19, 1942, the commission that conducted the tests rejected the GAZ-71 and recommended the SU-12 for adoption, taking into account the elimination of the shortcomings identified during the tests. However, further events developed according to a sad scenario widespread during the war years.
On December 2, 1942, the State Defense Committee decided to deploy the serial production of the SU-12, and by January 1, 1943, the first batch of 25 SU-76 vehicles (such an army designation received the "brainchild" of the 38th plant) was sent to the newly formed self-propelled artillery training center. Everything would be fine, but state tests of the new ACS began only on December 9, 1942, that is, after its mass production began. The State Commission recommended to adopt the artillery self-propelled gun into service, but again eliminating the shortcomings. However, few people were interested in this. As it happened more than once, our soldiers paid with their blood for the imperfection of the design of the combat vehicle.
Already after 10 days of military operation, most of the SU-76s showed breakdowns in gearboxes and main shafts. An attempt to improve the situation by strengthening the latter was unsuccessful. Moreover, the "modernized" self-propelled guns broke even more often. It became obvious that the SU-76 transmission had a fundamental design flaw - the parallel installation of two paired engines operating on a common shaft. Such a transmission scheme led to the occurrence of resonant torsional vibrations on the shafts. Moreover, the maximum value of the resonant frequency fell on the most intense mode of operation of the engines (driving in 2nd gear off-road), which contributed to their rapid failure. The elimination of this defect took time, which is why the production of the SU-76 was suspended on March 21, 1943.
In the course of the subsequent debriefing, the commission chaired by the head of the NKTP IM Zaltsman recognized SA Ginzburg as the main culprit, who was removed from office and sent to the active army as the head of the repair service of one of the tank corps. Looking ahead, let us say that Stalin, having learned about this decision, did not approve of it and ordered to recall the talented designer to the rear, but it was too late - Ginzburg died. However, even before leaving for the front, he proposed a solution that largely resolved the problem. Two elastic couplings were installed between the engines and gearboxes, and a friction slipping clutch was installed between the two main gears on a common shaft. Thanks to this, it was possible to reduce the accident rate of combat vehicles to an acceptable level. These self-propelled guns, which received the factory index SU-12M, went into production in May 1943, when production of the SU-76 resumed.
These self-propelled guns received their baptism of fire in February 1943 on the Volkhov front, in the Smerdyn area. Two self-propelled artillery regiments fought there - 1433 and 1434. They had a mixed composition: four SU-76 batteries (17 units in total, including the unit commander's vehicle) and two SU-122 batteries (8 units). However, such an organization did not justify itself, and since April 1943, self-propelled artillery regiments were equipped with the same type of combat vehicles: the SU-76 regiment, for example, had 21 guns and 225 servicemen.
It must be admitted that the SU-76s were not particularly popular with the soldiers. In addition to permanent transmission breakdowns, other layout and design flaws were noted. Sitting between two motors, the driver got fired up by the heat even in winter and went deaf because of the noise of two gearboxes that worked asynchronously, which was rather difficult to control with one stage. It was hard for the crew members in the closed armored wheelhouse, since the fighting compartment of the SU-76 was not equipped with exhaust ventilation. Its absence had a particularly negative effect on the hot summer of 1943. The tormented self-propelled gunners in their hearts called the SU-76 a "gas chamber". Already in early July, the NKTP recommended directly in the troops to dismantle the roof of the wheelhouse up to the apron of the periscope sight. The crews welcomed the innovation with joy. However, the life of the SU-76 turned out to be very short, it was replaced by a more reliable and sophisticated machine. As for the SU-76, a total of 560 of these self-propelled guns were manufactured, which were encountered in the troops until mid-1944.
STORM CONVERTIBLE
The new self-propelled gun appeared as a result of a competition announced by the leadership of the NKTP for the creation of a light assault self-propelled gun with a 76-mm divisional gun. GAZ and plant number 38 took part in the competition.
Gorky residents proposed a GAZ-74 ACS project on the chassis of a T-70 light tank. The vehicle was supposed to be equipped with one ZIS-80 engine or the American GMC and armed with a 76-mm S-1 cannon, developed on the basis of the F-34 tank gun.
At plant number 38, it was decided to use the GAZ-203 engine unit from the T-70 tank, which consisted of two GAZ-202 engines connected in series, as a power plant. Previously, the use of this unit on an ACS was considered unacceptable due to its long length. Now they tried to eliminate this problem through a more careful layout of the fighting compartment, changes in the design of a number of units, in particular the gun mount.
The ZIS-3 cannon on the new SU-15 machine was mounted without the lower machine. On the SU-12, this gun was installed with minimal changes, not only with the lower machine, but also with cut-off beds (on machines of later releases, they were replaced with special struts), which rested against the sides. On the SU-15, only the swinging part and the upper machine were used from the field gun, which was attached to a transverse U-shaped beam, riveted and welded to the sides of the fighting compartment. The conning tower was still closed.
In addition to the SU-15, Plant No. 38 offered two more vehicles - the SU-38 and the SU-16. Both of them differed in the use of the standard base of the T-70 tank, and the SU-16, in addition, in the fighting compartment, open on top.
Tests of new artillery self-propelled guns were carried out at the Gorokhovets training ground in July 1943 at the height of the Battle of Kursk. The SU-15 enjoyed the greatest success with the military, and it was recommended for mass production after some modifications. It was required to lighten the car, which was done by removing the roof. This simultaneously solved all ventilation problems, and also made it easier for the crew to board and disembark. In July 1943, the SU-15 under the army designation SU-76M was adopted by the Red Army.
The layout of the SU-76M was a semi-enclosed SPG. The driver sat in the bow of the hull along its longitudinal axis in the control compartment, which was located behind the transmission compartment. In the aft part of the hull there was a fixed, open top and partially rear armored wheelhouse, in which the fighting compartment was located. The body of the ACS and the casemate were welded or riveted from rolled armor plates with a thickness of 7–35 mm, installed at various angles of inclination. The armor of the gun's recoil devices was 10 mm thick. For the landing of the driver in the upper frontal sheet of the hull, a hatch was used, which was closed by a cast armor cover with a periscopic observation device borrowed from the T-70M tank.
To the left of the cannon sat the gunner of the gun, to the right - the commander of the installation. The loader was located in the rear left of the fighting compartment, the door in the stern sheet of which was intended for landing these crew members and loading ammunition. The fighting compartment was covered with a canvas awning from atmospheric precipitation.
In the front of the fighting compartment, a box-shaped cross member was welded, in which the support of the upper machine of the 76-mm ZIS-3 cannon of the 1942 model was attached. She had a wedge vertical breech and semiautomatic copy type. The length of the gun barrel was 42 caliber. Aiming angles - from -5o to + 15o vertically, 15o left and right horizontally. For direct fire and from closed positions, the standard periscopic sight of the gun was used (Hertz panorama). The rate of fire of the gun with the correction of the aiming reached 10 rds / min, with a cursory fire - up to 20 rds / min. The maximum firing range was 12,100 m, the direct-fire firing distance was 4000 m, the direct firing range was 600 m. The balance of the armoring of the swinging part of the gun was carried out by installing a 110-kilogram counterweight attached to the cradle from the bottom rear.
The gun ammunition included 60 unitary rounds. An armor-piercing tracer projectile weighing 6, 5 kg had an initial speed of 680 m / s, at distances of 500 and 1000 m, it pierced normally armor with a thickness of 70 and 61 mm, respectively. An armor-piercing sabot projectile weighing 3 kg and an initial speed of 960 m / s at distances of 300 and 500 m pierced 105-mm and 90-mm armor.
The auxiliary armament of the SU-76M consisted of a 7.62 mm DT machine gun, which was carried in the fighting compartment. For firing from it, loopholes in the sides of the wheelhouse and in its frontal sheet to the right of the gun were used, closed by armored flaps. DT ammunition - 945 rounds (15 discs). The fighting compartment also contained two PPSh submachine guns, 426 cartridges for them (6 disks) and 10 F-1 hand grenades.
In the middle part of the hull in the engine compartment, closer to the starboard side, the power unit GAZ-203 was mounted - two 6-cylinder GAZ-202 carburetor engines connected in series with a total capacity of 140 hp. with. The crankshafts of the engines were connected by a coupling with elastic bushings. The ignition system, lubrication system and power supply system (except for tanks) for each engine were independent. In the air cleaning system of the engines, two twin oil inertial air cleaners were used. The capacity of the two fuel tanks located in the control compartment is 412 liters.
The ACS transmission consisted of a two-disc main dry friction clutch, a ZIS-5 four-speed gearbox, a main gear, two multi-disc final clutches with floating band brakes and two final drives.
The undercarriage of the machine, applied to one side, included six rubberized road wheels, three support rollers, a front drive wheel with a removable gear rim and a guide wheel similar in design to the road roller. Suspension - individual torsion bar. The fine-link caterpillar of the pinned engagement included 93 tracks with a width of 300 mm.
The combat weight of the vehicle is 10, 5 tons. The maximum speed, instead of the calculated 41 km / h, was limited to 30 km / h, since with its increase the beating of the left axle shaft of the main gear began. Cruising in store for fuel: 320 km - on the highway, 190 km - on a dirt road.
In the fall of 1943, after the complete cessation of the production of light T-70 tanks, GAZ and plant number 40 in Mytishchi near Moscow joined the production of the SU-76M. On January 1, 1944, the Gorky Automobile Plant became the head enterprise for the SU-76M, and N. A. Astrov was appointed the chief designer of the ACS. Under his leadership, in the fall of 1943, work was underway at GAZ to improve the self-propelled gun and adapt its design to the conditions of mass production. Changes were made to the design of the SU-76M in the future. So, the machines of later releases received a high aft sheet of the fighting compartment with two embrasures and a larger door, a pipe welded to its right and left sides appeared to mount the machine gun in the aft part of the wheelhouse, embrasures of a new form, more adapted for firing from a machine gun, began to be used. etc.
Serial production of the SU-76M continued until 1946. A total of 13,732 self-propelled guns of this type were produced, including 11,494 before the end of the Great Patriotic War.
The SU-76M, like its predecessor, the SU-76, entered service with several dozen light self-propelled artillery regiments formed during the war. At the beginning of 1944, the creation of self-propelled artillery divisions began (each had 12, and later 16 SU-76Ms). They replaced individual anti-tank battalions in several dozen rifle divisions. At the same time, they began to form light self-propelled artillery brigades of the RVGK. These formations each had 60 SU-76M installations, five T-70 tanks and three American M3A1 Scout armored personnel carriers. There were four such brigades in the Red Army.
FROM "FEMALE" TO "COLOMBINA"
Speaking about the combat use of the SU-76M, it should be emphasized that at the initial stage these self-propelled guns, like all the others, were used quite illiterately, mainly as tanks. Most of the commanders of tank and combined-arms formations had no idea about the tactics of self-propelled artillery and often sent self-propelled artillery regiments literally to slaughter. Incorrect use, as well as the fact that at first the crews of self-propelled guns were staffed with former tankers (the comparison between a tank and a lightly armored self-propelled gun was clearly not in favor of the latter), caused a negative attitude towards the SU-76, which found expression in soldiers' folklore. "Mass grave for four", "pukalka", "old girl" - these were even the mildest nicknames. In their hearts, the soldiers called the SU-76M "bitch" and "naked Ferdinand"!
However, over time, the attitude towards this car has changed. Firstly, the tactics of application changed, and secondly, the crews who did not have a tank past looked at their vehicles in a completely different way. They did not consider it a disadvantage, for example, the lack of a roof. On the contrary, thanks to this, observation of the terrain was facilitated, it became possible to breathe normally (ventilation, as you know, was a big problem for Soviet tanks and closed self-propelled guns), it was possible to conduct long-term intensive shooting without the risk of suffocation. At the same time, unlike the ZIS-3 field gun, the SU-76M crew, thanks to the armor, was not hit from the sides and partially from behind by bullets and shrapnel. In addition, the lack of a roof made it possible for the crew, at least those of its members who were in the fighting compartment, to quickly leave the car if it failed. Alas, the driver remained a hostage in such a situation. The best protected, he died more often than other self-propelled gunners.
The advantages of the SU-76M include good maneuverability and low-noise running, reliability in operation (the GAZ-203 unit confidently worked out 350 hours of operation without serious breakdowns), and most importantly, the wide versatility of the machine. Light self-propelled guns were involved in counter-battery combat, supporting infantry in defense and offensive, fighting tanks, etc. They coped with all these tasks. The combat qualities of the SU-76M were especially in demand at the final stage of the war. Fast and agile, bristling with captured machine guns, the SU-76M was often included in the advance detachments when pursuing a retreating enemy.
Along with the attitude, the folklore also changed, reflected in the nicknames and names of combat vehicles: "swallow", "bold", "snowflake". The SU-76M began to be called a "crouton" and, quite aesthetically, was called a "columbine".
The SU-76M became the second largest Soviet armored combat vehicle of the Great Patriotic War. Only more "thirty-fours" entered the Red Army!
Light self-propelled guns were in service with the Soviet army until the early 50s. The last arena for their combat use was Korea. By the beginning of the war that broke out here 55 years ago, the DPRK troops had several dozen SU-76Ms. The Chinese "people's volunteers" also had these machines. However, the use of the SU-76M on the Korean Peninsula was not accompanied by great success. The low level of crew training, the enemy's superiority in tanks, artillery and aviation led to the fact that the SU-76M was quickly knocked out. Losses, however, were made up for by supplies from the USSR, and by the end of the confrontation, the North Korean units had 127 self-propelled guns of this type.
