“object 120” in the museum. Barrel 152 mm cannon M-69 barely fits into the frame.
By the mid-50s became obvious potential missile weapons in the fight against tanks, however, anti-tank guns still in no hurry to go back in time. another attempt to create a promising anti-self-propelled artillery with high power instrument was made. As part of the research project "Taran" was created SAU "Object 120" and 152-mm gun M-69 for her. In their combat characteristics of both samples surpassed all the developments of his time.
R & D "Taran»
In May 1957 g. several decrees of the USSR Council of Ministers of the course for the development of armored vehicles was asked to deal with enemy tanks. Industry was given the task to develop a number of armored vehicles from the guided missile weapons, and artillery installation tool with increased power. Creating ACS was conducted within the framework of research "Taran".
According to the technical project, new ACS must have had a mass of no more than 30 t and be protected from the shells of small and medium caliber. For self-propelled gun was necessary to create a large-caliber mass not exceeding 4,5 t with a range of a direct shot on goal of the "tank" in 3 km. At this distance the gun was punching 300 mm homogeneous armor meeting at an angle of 30 °.
The prime contractor on the "Taran" was the OKB-3 Sverdlovsk "Uralmash" headed by GS. Efimov. Design tools instructed Perm SKB-172 main designer M.Yu.. Tsyrulnykova. The shots were created in Moscow NII-24 under the leadership of VS. Kreneva and VV. Yavorsky. Several other organizations were involved in research on the rights of developers and suppliers of individual components and parts.
two guns
During the same 1957 , a number of organizations led by the SKB-172 was looking for the best tools to shape the future of ACS. calculations show, that the required ratio and firing characteristics masses can have gauge system 130 and 152,4 mm. By the end of the year SKB-172 fulfilled the preliminary design of two similar guns. The product caliber 130 mm obtained working designation M-68, and 152 mm instrument designated as M-69.
M-68 Draft proposed 130mm rifled gun with a barrel length 10405 mm (80 calibres) shot under separate-case charging. The calculated initial velocity of the projectile has reached 1800 m / s. tools for installing mass was 3800 kg - of 700 kg less than the maximum allowable under the technical project. To attack armored targets proposed using a specially designed armor-piercing projectile mass 9 kg. Its characteristics are consistent with the wishes of the customer penetration. Also it provides high-explosive shells with variable propelling charge.
The draft worked M-69 152-mm gun barrel with a smooth same dimensions. The relative length of the barrel - 68,5 calibres. Mass of product has reached the maximum allowable 4500 kg. Calculated maximum projectile speed was 1700 m / s. Anti-tank gun was used 11.5-kg armor-piercing projectiles or cumulative ammunition. Strengthening and manpower could attack the high-explosive fragmentation projectile.
Maket SAU «Taran»
In February 1958 g. at a meeting of the State Committee of defense equipment, taking into account the results of studies, changed the terms of reference. In particular, blank range at a target height 3 m was reduced to 2,5 km. Other requirements remain the same. Now, enterprises should produce and test two types of experimental gun.
Manufacture and subsequent shooting of the article M-68 and M-69 took about a year. Receiver group produced plant №172. Ammunition received from related companies. Tests were conducted on the plant using ballistic range setting M36-DR-3. During the test firings were able to confirm the basic performance characteristics of guns.
In March 1959, there was another meeting, which determined the final shape of the future ACS "Ram" or "Object 120". When choosing a self-propelled guns for the decisive factor was the nomenclature of ammunition. 130-mm cannon M-68 can only destroy tanks sabot projectile, while the M-69 and had a cumulative ammunition. Due to the greater flexibility of application to further development and application to "Taran" recommended smoothbore gun 152mm.
At the beginning of the next 1960 year "Uralmash" has received two experienced guns M-69 for installation on the "Object 120". Soon only a prototype self-propelled guns with weapons entered the factory tests.
Technical features
The finished product M-69, used as part of ACS, "Taran", It constitutes a smoothbore gun caliber 152,4 mm with a barrel length 9,045 m, utilizing separate-case loading. The breech of the gun was equipped with a semi-wedges. Near the muzzle was placed ejector. To partially compensate for recoil used muzzle brake with a slit-type 20 holes on each side.
Gun mounts had hydropneumatic recoil device with a resistance force 47 ts. Due to use of such devices and an efficient muzzle brake maximum recoil length was only 300 mm.
scheme «object 120» with a gun M-69
Vertical guidance of the swash with a gun by a hydraulic or manual drive. Angles crosstalk - from -5 ° to + 15 °. As part of the installation there was a mechanism, after each shot automatically returns the trunk at an angle loader. Gun unit is located in the tower of circular rotation, can fire in any direction.
"Object 120" was carrying ammunition from 22 rounds of separate loading. For faster delivery into a weapon projectiles and cartridges were placed in a drum packing. Due to this gun could perform 2 shot for 20 sec.
For the M-69 developed a number of shots for different purposes. To combat manpower and fortifications designed 152-mm high-explosive projectile mass 43,5 kg with propellant charge in 3,5 kg (reduced) or 10,7 kg (full). The fight against armored vehicles was provided by cumulative mass of the projectile and sabot 11,5 kg. Together with them, the sleeve used with a 9.8-kg charges.
The initial velocity of the projectile sabot - 1710 m / s. Blank range at a target height 2 m - 2,5 km. The pressure in the barrel has reached 4 thousand. kgf / cm². Muzzle energy - more 19,65 MJ. Effective range up to several kilometers.
On distance 3,5 km with a direct hit of a target projectile punched 295 gomogennoy booking. When the meeting angle 60 ° was reduced to penetrability 150 mm. at a distance 2 km gun could penetrate 340 mm (angle 0 °) or 167 mm (angle 60 °). At a distance of 1 km maximum table value penetration reached 370 mm.
In this way, the latest ACS "Object 120" with a gun M-69 could well affect any existing potential enemy armored vehicles at distances up to several kilometers. It should be noted, that in some characteristics 152 mm instrument from the beginning of the 60s can be compare with modern samples.
arrangement «object 120». You can evaluate the features of the gun accommodation
However, There were some notable shortcomings. Firstly, suffered self-propelled mobility, since a large barrel length increases the overall size armored vehicles. Despite the stern accommodation of the crew compartment, the muzzle of the barrel a few meters beyond the holder. When driving on rough terrain it threatened utykaniem trunk into the ground with unpleasant consequences.
End of the "TAR"
Tests ACS "Object 120" with a gun M-69 started in early 1960 year and lasted only a few months. Already 30 May the Council of Ministers decided to discontinue work on "TAR" in view of the expected obsolescence. At the same industry it has the task to develop a new 125-mm tank gun with enhanced characteristics. The outcome of this project was the smoothbore gun 2A26 / D-81. In parallel with it developed new anti-missile systems.
No longer need experienced "Object 120" was sent to storage. Later, he got into a museum of armored vehicles in Kubinka, where now he can see everyone. This ACS immediately attracts the attention of long-barreled, hanging over the tracks for visitors. Even without a muzzle brake gun M-69 almost reaches the opposite row of armored vehicles.
With the closing of research "ram" operation on 152-mm smoothbore guns for combating tanks stopped for a long time. New projects such weapons have appeared only in the eighties, when there was a need to increase the firepower of the main tanks. However, this trend still has not produced tangible results and did not affect the re-troops.
152-mm smoothbore gun M-69 development SKB-172 was one of the most powerful guns of your time and can guarantee to solve tasks. However, even before the completion of the tests it was decided to support the refusal of large caliber in favor of more compact systems. Nevertheless, Gun M-69 and ACS "Object 120" during the tests were able to demonstrate the highest specifications, by which occupied an important place in the history of Russian arms and military equipment.
/Kirill Ryabov, topwar.ru/
