In 1957, work began in our country to create several promising armored vehicles designed to combat tanks the enemy. "Topic number 9", set by the resolution of the Council of Ministers, provided for the creation of a self-propelled anti-tank gun with the code "Taran". The result of this project was the appearance of self-propelled guns "Object 120" or SU-152, the work on which was stopped at the stage of factory tests.
The development of the product “120” was carried out in SKB Uralmashzavod under the leadership of G.S. Efimova. The gun was ordered SKB-172, headed by M.Yu. Tsirulnikov. Other enterprises were involved in the project. In 1958, they determined the final look of the future self-propelled guns, after which the development of a technical project began. In 1959-60. assembly of experimental guns and self-propelled guns was carried out.
“Object 120” was completed on the basis of the existing self-propelled gun SU-152P with the replacement of part of key units. The chassis with the armored body of the front-engine layout and the caterpillar undercarriage has survived. In the aft part of the hull there was a fighting compartment, made on the basis of a full-swing turret. Reservation of the car consisted of rolled and cast parts up to 30 mm thick, providing protection from 57-mm shells.
The power unit included a V-105-V diesel engine with a capacity of 480 hp. With the help of a mechanical two-line transmission, power was supplied to the front-wheel drive wheels. The self-propelled guns retained a seven-roller chassis with a torsion bar suspension capable of withstanding a recoil momentum. A 27-ton armored vehicle could reach speeds of more than 60-62 km / h and overcome various obstacles.
Projections of self-propelled guns. Figure Russianarms.ru
The turret housed an M69 smoothbore gun of 152,4 mm caliber with a barrel length of 9045 mm (59 klb) and a muzzle brake, capable of using several types of separate-shell loading charges. Due to the pressure in the channel up to 392 MPa, the acceleration of the armor-piercing projectile to 1710 m / s was ensured. The shots were transported in a drum, accelerating the loading process. Ammunition included 22 shells with shells. High-explosive, sub-caliber, and cumulative shells could be used.
Additional weapons "Taran" included anti-aircraft machine gun CPV; the machine gun coaxial with the gun was missing. In case of emergency, a crew of four had a pair of machine guns and a supply of hand grenades.
At the beginning of 1960, Uralmashzavod completed the construction of the experimental “Object 120” and completed part of the factory tests. Before their completion, after work on the tracks and at the shooting range, the project was closed. The customer considered that a self-propelled anti-tank gun is not of interest to the army - unlike promising missile systems of a similar purpose.
Advantages and disadvantages
In accordance with the terms of reference for the "Taran" ROC, the self-propelled gun was supposed to show a range of a direct shot of 3000 m. From this distance, it was required to penetrate at least 300 mm of homogeneous armor at an angle of 30 °. These requirements were generally fulfilled. When fired from 3 km, the M69 cannon with a sub-caliber projectile (weight 11,66 kg) could penetrate a 315-mm vertical armor plate. With an inclination of 30 ° - a plate with a thickness of 280 mm. High armor penetration persisted at increased ranges.
Thus, the “Object 120” was able to hit in the frontal projection all existing medium and heavy tanks of a potential enemy at ranges of kilometers, i.e. from outside the range of the return effective fire. The developed cumulative ammunition made it possible to obtain sufficient characteristics, and 43,5 kg high-explosive fragmentation expanded the combat capabilities of self-propelled guns.
High firepower was also provided by successful reloading facilities. The gun after the shot returned to the loading angle, and drumming simplified the work of the loader. Due to this, the crew could make up to 2 shots in 20 seconds. In this regard, the SU-152, at least, was not inferior to other vehicles with artillery weapons, including smaller calibers.
The disadvantage of "Object 120" could be considered a relatively low level of protection. The most powerful sections of the hull and turret had armor only 30 mm thick, which protected only from small and medium caliber shells. The hit of ammunition from 76 mm and above threatened with the most serious consequences. However, this feature of the self-propelled guns was not considered a disadvantage due to the low probability of enemy fire from ranges of 2,5-3 km.
Also not quite successful, although forced, were the overall parameters. Despite the aft location of the fighting compartment, the barrel stood out in front of the hull for several meters. This made it difficult to drive on difficult terrain or could even lead to various unpleasant incidents, including with temporary loss of combat capability.
"Taran" in the museum. Even with the muzzle brake removed, the M69 gun does not fit well into the allocated space. Wikimedia Commons Photos
In general, the "Object 120" was a fairly successful anti-tank self-propelled guns for its time with high characteristics that meet the requirements of the time. However, some features of this self-propelled guns could impede operation; others promised rapid obsolescence, as the tanks of the probable enemy developed.
Taran vs. Dragon
The same Decree of the Council of Ministers in 1957 set “theme number 2” - the development of a tracked armored vehicle with specialized anti-tank missile weapons. The result of this project was the self-propelled ATGM "Object 150" / "Dragon" / IT-1, created by Plant No. 183 in collaboration with OKB-16 and other enterprises.
"Object 150" was a substantially redesigned T-62 tank with full-time armor and a power plant, but with a complete replacement of the equipment of the fighting compartment. Inside the machine were styling and a feed mechanism for 15 guided missiles, as well as a retractable launcher. There were also optical and computing tools for finding targets and firing control.
Weapon "Dragon" was a 3M7 missile 1240 mm long with a diameter of 180 mm and a mass of 54 kg. The rocket had a solid fuel engine and developed a speed of 220 m / s. The guidance system is a semi-automatic radio command with the calculation of data on-board equipment of an armored car. Firing was provided at a range of 300-3000 m. The cumulative warhead of the rocket pierced 250 mm of armor at an angle of 60 °.
IT-1 with a rocket in combat position. Photo Btvt.info
After completing part of the work on two projects, the customer had to compare fundamentally different military vehicles of the same purpose - and choose a more successful and promising one. As it turned out, there was no clear leader in such a comparison - both samples had advantages over each other.
In terms of mobility, both anti-tank systems were equal. In terms of protection, the Object 150 was the leader on a tank chassis with appropriate armor and a smaller frontal projection. The use of a chassis with a mass of ready-made units simplified the future operation of the "Dragon" in the troops.
In combat qualities, a clear leader was absent. Over the entire range of operating ranges, IT-1 could show at least not the worst armor penetration or even surpass the "Taran" - due to stable indicators of the cumulative charge. An important advantage was the availability of missile controls for more accurate shooting. Finally, the weapons did not protrude from the hull and did not spoil the patency.
On the other hand, the SU-152 had no restrictions on the minimum firing range, could use shells for various purposes, carried more ammunition and showed better rate of fire. In addition, artillery shells were much cheaper than guided missiles. As for less armor penetration at long distances, it was enough to destroy typical targets.
View from a different angle. Photo Btvt.info
An analysis of the possibilities and prospects of the two facilities was carried out in the spring of 1960, and on May 30 its results were consolidated by a new resolution of the Council of Ministers. This document demanded to stop work on the project "120" - despite the fact that the self-propelled gun barely had time to go to factory tests. The finished sample was later transferred to storage in Kubinka, where it remains to this day.
For further development, followed by arming recommended "rocket tank" IT-1. Work on it took several more years, and only in the mid-sixties he went into a small series and got into the troops. Less than 200 such armored vehicles were built, and their operation lasted only three years. Then the idea of a missile tank was abandoned in favor of other concepts.
Reasons for failure
Most often, the rejection of “Object 120” in favor of “Object 150” is explained by the specific views of the country's leadership, which paid increased attention to missile systems, including to the detriment of other areas. This explanation is logical and plausible, but, apparently, other factors affected the fate of anti-tank self-propelled guns.
One of the main factors that influenced the fate of the SU-152 may be its own technical features. It is easy to notice that the highest combat characteristics of the "Taran" were provided, first of all, by the growth of caliber and barrel length, which led to noticeable limitations and problems. In fact, the result was a “self-propelled limit parameters,” capable of producing high rates, but with minimal potential for modernization.
IT-1 also could not be called an ideal machine, but at that time it looked more successful and had better prospects. In addition, the concept of anti-tank systems on a self-propelled armored platform fully paid off and was developed. Similar samples, although not on a tank base, are still being developed and put into service.
In the sixties, after the abandonment of the "Object 120" / "Taran", the development of a new generation of smooth-bore tank guns of 125 mm caliber and ammunition for them began. Its result was the product D-81 or 2A26 and a whole line of shells for various purposes. The resulting set of weapons in terms of performance was at least as good as the Taran and the Dragon. At the same time, it could be widely used on tanks of new models. Subsequently, the famous 2A26 was created on the basis of 2A46.
The emergence of new tank weapons made it futile to further increase the caliber of self-propelled guns in the type of project "120". At the same time, tank guns did not interfere with the further development of anti-tank missiles, and then they themselves became launchers for such weapons. Large caliber remained with howitzer artillery, including self-propelled. However, the idea of a 152 mm anti-tank gun was still being returned, but already in the context of tank weapons.