2S3 M-1973 Akatsiya (Acacia)
152-mm Self-Propelled Gun-Howitzer
The 2S3 comprises a modified version of the 152-mm towed howitzer D-20 and a chassis similar to the SA-4/GANEF launch vehicle. The thick tube extends beyond the front of the hull by the length of the double-baffle muzzle brake. It differs from the D-20 by the addition of a bore evacuator just behind the muzzle brake and, in travel position, it is supported by a brace attached just behind the bore evacuator. The running gear differs from that of the SA-4 in that it has only six road wheels (with spaces between the three front wheels only) and different spacing between the four support rollers.
On July 4, 1967, the Central Committee of the CPSU and the Council of Ministers of the USSR adopted a joint resolution prescribing to begin the development of a new 152-mm self-propelled howitzer. According to which began full-scale work on the ACS "Acacia", "Carnation", "Violet" and the 240-mm self-propelled mortar "Tulip". The design and manufacture of the first prototypes of the artillery unit of the 152-mm self-propelled howitzer 2S3 "Akatsiya" took place in Sverdlovsk, in the OKB-9 plant named after V.I. MI Kalinin, and the chassis - at the plant "Uraltransmash".
The artillery unit of the ACS was developed on the basis of the D-20 towed howitzer-gun designed by I.F. Efimova. Its barrel was made monoblock, with an ejector. The internal structure of the barrel, ballistics and ammunition were taken from the D-20 without changes. Also, a two-chamber muzzle brake and a vertical, wedge gate with a semiautomatic mechanical (copy) type were introduced. The new howitzer received the factory index D-22 and the GRAU index (Main Missile and Artillery Directorate) - 2A33. The chassis was developed on the basis of the Krug air defense missile launcher, which in turn was created on the basis of the experimental CAU SU-100P, and received the index "Object 303".
The first two prototypes of the 2S3 were manufactured at the end of 1968. During factory tests, which ended in October 1969, excessive gas contamination of the fighting compartment was revealed, especially when firing with small charges. For the same reason, four more samples, released in the summer of 1969 for field tests, were not accepted. Therefore, it was decided to replace the separate-sleeve loading with a cartridge one and introduce a semi-automatic piston bolt with a plastic obturator. The problem of gas pollution was dealt with, and in 1971 the ACS 2S3 "Akatsia" was put into service.
The hull and turret of the vehicle are welded from rolled armor plates and protect the crew from bullets and shrapnel. Structurally, the body is divided into three compartments: engine-transmission (front right), control (front left) and combat (rear). The control compartment is located in the bow of the hull between the port side and the engine bulkhead. It houses the driver. The power compartment is located on the right in the bow. It houses the engine, transmission, fuel and air supply, lubrication, cooling, heating and starting systems. The fighting compartment occupies the middle, aft part of the hull and the entire turret, which is an all-welded structure. A commander's cupola and commander's hatch are installed in the roof of the tower on the left, and a loader's hatch on the starboard side. The so-called basket is attached to the bottom of the tower, in which the crew of the fighting compartment and part of the ammunition are located. The tower, together with the basket, is placed in the body with the help of a ball running device.
The hull and turret of the vehicle are welded from rolled armor plates and protect the crew from bullets and shrapnel. Structurally, the body is divided into three compartments: engine-transmission (front right), control (front left) and combat (rear). The control compartment is located in the bow of the hull between the port side and the engine bulkhead. It houses the driver. The power compartment is located on the right in the bow. It houses the engine, transmission, fuel and air supply, lubrication, cooling, heating and starting systems. The fighting compartment occupies the middle, aft part of the hull and the entire turret, which is an all-welded structure. A commander's cupola and commander's hatch are installed in the roof of the tower on the left, and a loader's hatch on the starboard side. The so-called basket is attached to the bottom of the tower, in which the crew of the fighting compartment and part of the ammunition are located. The tower, together with the basket, is placed in the body with the help of a ball running device.
The main part of the fighting compartment is occupied by a howitzer, ammunition racks and crew jobs. The gunner's seat is located to the left of the howitzer, and the loader's seat is to the right. The commander is located behind the gunner. The artillery unit consists of a 152-mm D-22 howitzer, which allows firing with indirect and direct fire from a place when ammunition is supplied from both the ammunition rack and from the ground. Hydraulic recoil brake - spindle type, with fluid compensator; knurler - hydropneumatic, with additional braking valve. The recoil and recoil brake cylinders are rigidly connected to the breech and retreat with it when fired. The lifting mechanism of the sector type, with a manual drive, provides elevation angles of the trunk from - 4 ° to + 60 °. The swivel mechanism is used for circular rotation of the tower; there is a pneumatic balancing unit.
The "Akatsia" ammunition uses separate-case loading shots, placed in two ammunition racks, in the turret and inside the hull. It includes high-explosive fragmentation projectiles OF-25, OF-540 and OF-540ZhS, the latter with a metal-ceramic leading belt; cumulative BP-540 weighing 27.4 kg and with special 5.6-kilogram charges, providing an initial speed of 676 m / s. At an angle of encounter with a target of 90 °, they pierce armor with a thickness of 250 mm, and at 60 ° - 220 mm. Also used are armor-piercing sharp-headed projectiles Br-540 and blunt-headed Br-540B, with a ballistic tip, which, at a distance of 1000 m, when hitting an object at an angle of 90 °, penetrate armor up to 120 mm thick. In addition, the use of ammunition for towed ML-20 cannon-guns, D-20 cannon-howitzers and D-1 howitzers, including concrete-piercing G-545 and special ones, is allowed.
The turret houses the gun, part of the ammunition and the filtering unit. The commander's cupola is equipped with a 7.62 mm PKT anti-aircraft machine gun. In the rear of the vehicle there is a special hatch for loading shells. 2S3 "Akatsia" is equipped with a filtering unit, an automatic fire-prevention system that turns on when the temperature rises in the combat or power compartments, and a system for sealing the manned compartments to protect the crew from the damaging factors of chemical, bacteriological and nuclear weapons. In the latter case, it is triggered automatically when streams of gamma radiation appear during a nuclear explosion. If necessary, the tightness of the "Acacia" is maintained both on the march and when firing ammunition inside the vehicle.
The engine-transmission compartment is equipped with a 12-cylinder, 4-stroke V-59 diesel engine with a power of 520 hp. - water cooling, with forced fuel injection and the ability to work on afterburner. The transmission is mechanical, two-line, the gearbox is made in a block with a planetary swing mechanism. Suspension - independent, torsion bar, with telescopic hydraulic shock absorbers. Tracks with rubber-metal hinges. The driver sits in the left front of the vehicle, with the engine located on the right side. The commander sits at the left center of the turret, with the gunner in front of him. The loader is at the right side of the turret. A hatch in the rear of the hull is used for loading ammunition. There is also a large hatch on the right side of the turret for loading ammunition and discarding expended brass. A 7.62-mm machine gun is located on the commander's cupola.
The 2S3 provides highly mobile, all-terrain fire support for motorized rifle and tank divisions. Its maximum range with a normal round is the same as that of the 152-mm towed howitzer D-20 (17,230 meters), and it probably fires a RAP round, increasing its range to about 30,000 meters. The 2S3 has a speed of up to 50 km/hr; but, unlike the 122-mm self-propelled howitzer 2S1, it is not amphibious.
Because of the twin recuperators above the tube, the elevation is restricted to +63 degrees. Armor is thin-skinned, providing only a minimum of protection for the four-man crew.
The 2S3 was first introduced into the Soviet inventory in 1973 and also has been known under the provisional designation M1973. It is also known simply as the SP-73 or SAU-152 (and erroneously as the M1975 or M-75). It somewhat resembles the US 155-mm self-propelled howitzer M-109.
By the mid-1980s the 2S3 had begun to replace the D-20 in the howitzer battalions of artillery regiments and brigades at front and army level. Since its introduction, the 2S3 gradually replaced the towed 152-mm howitzer D-1 (M1943) in the artillery regiment of motorized rifle divisions and one battalion of the towed 122-mm howitzer D-30 in the artillery regiment of tank divisions. Also, the 2S3 replaced some towed 152-mm artillery in the front-level artillery division and in the army-level artillery regiment/brigade.
The 2S3M is an upgrade version of the 2S3. In 1975, instead of two mechanized ammunition racks, one was introduced - a drum type for 12 shots, which made it possible to increase the ammunition load from 40 to 46 shots. The self-propelled gun upgraded in this way received the 2S3M index, and the howitzer - 2A33M. The 2S3M turret contains the 2A33 cannon, fire-control equipment, ammunition storage space, and work positions for commander, gunner, and loader. The cannon extends beyond the vehicle front and has an electrical loader/rammer attached to the cradle. Ammunition is stored in the rear of the chassis and can be replenished through a hatch in the rear panel.
In the late 1970s, the ACS were upgraded to the 2S3M standard, and then the 2S3M1, receiving a new fire control system and communications equipment. In 1987, the howitzer was improved again. It was equipped with equipment for receiving and displaying fire control information and a new SP-538 sight. In ammunition, a guided projectile OF-38 "Krasnopol" appeared, which makes it possible to hit objects moving at speeds up to 35 km / h at a distance of up to 18 km. This installation was named 2S3M1.
The last deep modernization of the 2S3 was designated 2S3M2. The changes affected the artillery unit of the self-propelled howitzer. The 2A33 howitzer has been replaced with a more powerful 152.4 mm howitzer 2A33M (the export version provides for replacement with a 155 mm M-385 howitzer), which gave an increased firing range compared to previous versions. In addition, the automated guidance and fire control system ASUNO has been added. The security of the vehicle has been improved thanks to the installation of the 902B system for setting up smoke screens.
In 2004-2009, part of the Akatsy was upgraded to the 2S3M2 level. Despite its age, the Akatsiya self-propelled gun is still one of the main artillery systems of the Russian army. The mass of the modernized ACS is 27 tons, the effective fire range is from 17 to 20 km, depending on the type of ammunition. The main purpose is the destruction of artillery, tanks , self-propelled guns and other armored equipment, the destruction of field and long-term defensive structures.
Uraltransmash (part of the Uralvagonzavod concern of the Rostec state corporation) delivered the first batch of 2S3M Akatsia self-propelled artillery units (ACS) 2S3M Akatsiya to the Russian Ministry of Defense as part of the state defense order. This was reported to TASS on 13 May 2021 in the press service of UVZ. "The vehicle has improved communication facilities, and also carried out work on complete import substitution. Self-propelled howitzers are fully equipped with transportable spare parts, tools and accessories and handed over to the customer," the press service quoted Dmitry Semizorov, General Director of Uraltransmash, as saying.
The ACS "Akatsia" transferred to the Ministry of Defense underwent major overhaul and modernization. The details of the modernization were not disclosed, it is stated that all imported components have been completely replaced on the machines, and new communications have been installed. How many vehicles in the transferred batch are not reported, it is noted that this is the first transfer to the military that have undergone overhaul with the modernization of the ACS 2S3M2 "Akatsia". All work was completed on time within the framework of the state defense order.
