In September 1931, the government of the USSR set the task of preparing a mechanical mobile base for artillery of large caliber and high power to the state union enterprise "Spetsmashtrest" by the government of the USSR.
History of creation
This organization had to report to the USSR GRAU before the beginning of May 1932 on the implementation of projects of two artillery "triplexes". The first of them - for corps artillery, consisted of a complex of 107 mm guns of 1910 / 1930, 152 mm howitzers of 1909-1930. and 203, 2 mm howitzers, and the second - for special artillery formations of high power, which included. (130) 152 mm howitzer cannon, 203, 2 mm howitzer and 305 mm mortar.
The projects were reported on time, and the chassis of a heavy tank, which was being created at that time, was used as an engineering solution for the chassis. For the manufacture of the "hull" version of the complex, the government allotted two years, and the complex of high power did not yet have the necessary armament created by that time (there was no 152 mm howitzer gun and 305 mm mortar). Therefore, only the howitzer version of the complex, equipped with a 203, 2 mm B-4 howitzer, remained for work.
Creation of SU-14
The year 1933 was marked by the beginning of the design and manufacture of "self-propelled guns" of increased power "triplex TAON", which was further called SU-14. The work was carried out under the direction of the designer PI Syachintov. The first version of the base for the guns was ready at the end of the spring of 1934, but due to transmission defects, the chassis refinement lasted until the end of the summer of 1934.
The body of the self-propelled gun was made of rolled armor plates 10-20 mm thick, welded and riveted. The location of the driver is on the left side of the side in the front of the self-propelled gun. He monitored through inspection hatches. The remaining six members of the crew were located in the stern on special chairs.
SU-14 device
The main type of armament is the 203, 2 mm B-4 howitzer of 1931. with the unchanged upper cradle and the mechanisms for lifting and turning the implement. To conduct aimed fire, an optical panorama of the Hertz system was used. The self-propelled gun used additional weapons in the amount of 3 DT machine guns of 7, 62 mm caliber, which could be located on 6 brackets on the sides of the combat vehicle. One machine gun could be mounted in the anti-aircraft version on the front of the self-propelled gun. The ammunition carried was 8 rounds of separate-cartridge loading and 36 disks (2268 rounds) for the DT machine gun.
To simplify the loading process, the self-propelled gun was equipped with two lifting devices with a lifting capacity of 200 kgf. The shot was fired with a stationary firing unit, while the self-propelled gun was strengthened in the ground with the help of openers, which were retrofitted with hydraulic cylinders, both with manual and electric drives. Angles: elevation of the gun from +10 to +60 degrees, turning - 8 degrees when the self-propelled gun is stationary. The maximum firing range is -18000 meters. The transfer time from the traveling state to the firing position is up to 10 minutes. Rate of fire 10 shots in 60 minutes.
The combat vehicle was equipped with a 500-horsepower 12-cylinder V-shaped gasoline engine M-17, which was equipped with two KD-1 carburetors of the "Zenith" type. The engine was started with a Scintilla starter and the ignition system was equipped with a 24-volt magneto system with a starter that also used magneto. The fuel range was 120 km with a fuel system capacity of 861 liters.
The transmission elements were a 5-speed manual transmission, which was aggregated with a system of main and auxiliary clutches. It also included a power take-off for the ventilation system and two uniquely designed final drives. Air for cooling the product systems was supplied from an axial fan and exited through lattice side hatches.
The suspension of the combat vehicle was spring, candle type, attached to the lower sides of the self-propelled gun. To reduce the load on the suspension during firing, it was turned off. The undercarriage on only one side consisted of 8 medium-diameter road wheels, 6 carrier rollers, a rear idler and a front drive wheel with hooks for tracks. All components were taken from the chassis of the T-35 heavy tank, which was equipped with external shock absorption. The idler wheels were made with a metal band, which proved to be better than rubber.
The electrical wiring of the combat vehicle is made according to a simple electrical circuit. Mains voltage -12 volts, power sources - 2 starter batteries 6-STA-1X with a capacity of 144 A / h in series connection with the Scintilla generator operating from a voltage of 24 V.
Testing SU-14
Failures began from the moment they moved to the artillery range (NIAP). During the transportation of the product, several tracks burst, extraneous noises appeared in the checkpoint, the engine began to overheat, and therefore the test march with equipment for 250 km was postponed to a later time.
The artillery fire received a satisfactory assessment, although serious shortcomings were also revealed: during firing, the deck (the name of the working platform of the SU) was constantly in motion, vibrated, it was possible to stay on it only if you firmly hold on to the handrails and railings. The rate of fire did not meet the requirements, the ammunition lifting system turned out to be unreliable.
After eliminating the shortcomings, the field tests were repeated. The self-propelled guns arrived at the test site modified, the tracks were reinforced, the cooling system was improved. This time, the tests began with checking the base of the self-propelled gun for road characteristics. At 34 km, the checkpoint was out of order due to a defect. During firing at various elevation angles and other additional conditions, many flaws were revealed, due to which the acceptance of self-propelled guns in this form by the state commission became impossible.
After completing the revision, in March 1935, the prototype was submitted for testing. Unfortunately, the work carried out affected only the chassis and the engine-transmission part (the clutches and gearbox of the T-35 tank were installed). The artillery complex has hardly undergone any changes. Dynamic tests were carried out, during which a good result was obtained, although breakdowns followed this model at this stage. It was found that through the holes in the armor, which were prepared for the DT machine guns, firing does not represent a tactical opportunity. It was also impossible to use the transportable ammunition, the stowage of which was under the mount of the gun "in a marching way".
Based on the data obtained during the implementation of the SU-14 project, the units and mechanisms of the new modification of the SU-14-1 were designed, the prototype of which was assembled at the beginning of 1936. In its updated design, the model had a modernized gearbox, clutches, brakes and other improvements, the exhaust pipes were moved away from the driver, and the opener fastening system was improved.
The main gun remained the same - the 203, 2 mm B-4 howitzer of the 1931 model. Ammunition also has not changed. It was supposed to use the "Comintern" tractor, which was produced at KhTZ, as such a tractor-carrier of ammunition. In the event of an emergency, two tractors could deliver the ACS to a repair agency. The ammunition load of the DT machine guns was reduced by 2,196 rounds.
There were no visible changes in the armored frame, with the exception of a decrease in the thickness of the hinged side from 10 to 6 mm. The model received a modified forced version of the M-17T engine, which increased the speed of the 48-ton product to 31.5 km / h. In the suspension, thicker leaf springs were used and the mechanism for disabling the suspension during firing was removed. Artillery tests were carried out at NIAP.
In December 1936, 152-mm artillery systems U-30 and BR-2 were brought from the Uralmash plant and the Barrikady plant to test the cannon version of the hull complex. At the same time, rearmament to other systems took place, and testing of complexes with new guns began, which in February 1937 received a positive assessment. In the planned measures for 1937, it was planned to manufacture a trial series of 5 combat vehicles SU-14 BR-2 (with 152mm Br2), and from 1938 the product was supposed to go into the "series".
At the same time, by the middle of 1939, it was planned to manufacture a 280mm self-propelled gun SU-14 Br5, but they tried to forget about the SU-14 B-4 howitzer, because its developer-leading designer of the Bolshevik plant Mandesiev was recognized as an “enemy of the people”. Soon the creator of the SU-14 Syachint was arrested under a similar article, and this technique was forgotten for a while. Two ready-made self-propelled guns were transferred to the GRAU warehouse.
At the end of 1939, during the war with the White Finns, the Red Army began an assault on the well-prepared defensive belt of the Finnish army, which was named the Mannerheim Line by the name of its creator. It was a perfectly prepared defensive complex, which was designed to hold the line of defense even with the use of heavy artillery. It was here that our military specialists remembered the story of heavy self-propelled guns. These two self-propelled guns were removed from the museum sites and, by a decree of the State Defense Committee of the USSR, were sent for revision to plant No. 185 (the former experimental plant of Spetsmashtrest). However, in the course of underdelivery of the necessary components and other delays, two ACS were ready when the Finnish company had already ended.
But in the history of Soviet heavy weapons, these interesting products managed to leave a mark: in the fall of 1941, during the defense of Moscow, both SU-14s, as part of a separate battalion of special-purpose heavy artillery, were used to deliver artillery strikes against the advancing parts of the Wehrmacht.
So today in Kubinka there is a SU-14-1 equipped with a 152 mm Br-2 gun.