INTRODUCTION:
The 2S7 Pion (Peony – most Self-Propelled guns are named after trees or flowers, not unlike America's "Peace Keeper" missiles :-) , is a huge weapon and has the longest range of fire compared with any other modern field artillery unit. It is also the largest self-propelled artillery gun in the world . While it is only partially armored and weighs 50.7tons/46-mt, it is 43' 3”/12.8 ~13.20-meters long (the hull is 10.5 meters alone), 11' 1” /3.5~3.38-meters wide and 9' 10”/3~3.5 meters high. That roughly translates into 366mm x 100 mm x 100 mm in 1/35 scale, the 2A44 itself is huge – barrel length is 11240 mm (321 mm in scale).
The design of the 2S7 gained momentum in response to The 6 Day War of 1967 to counter the success that the Israelis were having using their American made 175-mm M107s in the counter battery fire versus the Egyptian forces in the fight over the Suez Canal. New objectives were, to build a gun that would be able to outrange the enemy artillery and engage them with both conventional, as well as the nuclear and chemical rounds. The new weapon, dubbed Article 216, while under preliminary development by the end of 1967, was developed in two different directions:
• Article 216sp1 used components of the T-10 heavy tank and a V-2-type diesel engine;
• Article 216sp2 used the driveline of the T-72 tank but with the running gear of the T-80 series tanks (individual, torsion with stopping hydro absorbers); though with 7 road wheel stations and six track-return rollers (that support the inside of the track only) for the longer hull. Chief designer was N. S. Popov, who was the head of KB-3, the descendent of the Kotin design bureau in Leningrad, and who was also developing the T-80 series tanks at the same time.
Both variants were combined with the massive 2A44 203mm gun, designed by the famous "Barrikady" factory in Volgograd (Stalingrad.) The later variant, Article 216sp2, won out and was fully developed with it's V-46-1, the V-type 12-cylinder diesel engine completed with turbocharger; reaching a maximum power of 750 hp. The official designation SO-203(2S7) is its GRAU designation. It was identified for the first time in 1975 in the Soviet army and so was called M-1975 by NATO (the 2S4 Tyulpan also received the M-1975 designation). One brigade of 72 of these guns became part of the 34th Artillery Division in GSFG during the late 70's. Later, this chassis was used to develop and improve a number of other heavy vehicles.
The cabin protrudes forward creating counterweight for the main gun. This fully enclosed crew compartment has seats for the commander, driver and two other crew members. The commander and driver are each provided with a circular roof hatch and in front of these are periscopes for forward observation. In front of them are windows that, when in a combat area, are covered by an armored shutter hinged at the top. In addition, there is a single forward-facing periscope in the forward part of the roof between the commander and driver. The torsion bar suspension has seven dual rubber-tired road wheels either side with the drive sprocket at the front and the idler at the rear(lowered to the ground in combat order),... looking like a backwards tank hull. Along either side of the hull are a series of large stowage boxes, along with the 203-mm gun, which is not fitted with a fume extractor or a muzzle brake, being mounted at the rear. One piston of the recoil brake and recuperator is located on the gun with the other two pistons beneath it and these limit recoil to a maximum of 140cm/4.6ft. The 2A44, when traveling is held in position by a manually operated lock mounted on top of the cab. Mounted at the very rear of the 2S7 is a large hydraulically operated spade that is lowered to the ground before firing commences. This spade digs in the ground approximately 700mm/28in and provides good fire stability. Standard equipment includes tank internal communication device, radio equipment, fire prevention equipment, an NBC system of the overpressure type and night vision equipment.
2S7 had its advantages and disadvantages.
• The advantages were long range ( 23.3-miles/37.5-km with the regular HE round, while the nuclear round had a minimum of 11.2-miles/18-km, and a maximum range of 18.6-miles/30-km.The RAP round could go all the way to 34.2-miles/55-km). with this reach it had the ability to deploy and leave the firing position in short order; that upon inception, made it impervious to counter battery fire. Its fairly high speed (31mph /50 Km/h ) and good cross country mobility, allowed it to keep up with armored columns.
• The disadvantages were very high cost and large size (Length 13100M Width 3380m Height 3000m ), absence of the turret and limited traverse ( Elevation range is between 0 degrees and 60 degrees and traverse range is 30 degrees (only 15 degrees to each side)., only carring 4 rounds for immediate use, as well as low rate of fire; 1.5-round per minute. This was later improved to 2.5-rounds per minute on the 257M.
If you know of any changes or updates to this information ...Please let me know.
~Cheers
