1943 T-34/85

The genesis of the T-34-85
The State Defense Committee met on August 25, 1943, following the battle of Kursk, and decided to upgrade the T-34 with a new gun. The T-43 was dropped in order to not have to completely retool the production lines relocated at such great price to the foothills of the Ural mountains. But at the same time, this posed a real challenge to the engineers, who had to conceive a new turret capable of housing the long-barreled 52K model 39, the standard anti-aircraft gun of the Red Army at the time, without touching the lower part of the tank, chassis, transmission, suspension or engine. Choosing this gun was a bold move, clearly influenced by the heavy toll imposed by the German 88 mm (3.46 in) on every front since the beginning of the war. In the endless race between firepower and protection, it became apparent that no engine of the time could give a tank, with sufficient protection from the German 88 mm (3.46 in), the minimal mobility requirements put up by the Red Army. The original T-34/76 seemed to have the perfect balance of speed, armour and firepower at first, but since by 1943 its firepower was limited and something had to be changed, protection was sacrificed. On the other hand, keeping the T-34 virtually unchanged except the turret could provide the assurance of a quick transition, almost uninterrupted, between the two types, which was just what the Stavka required to keep the edge in terms of numbers.

Design of the T-34-85
Gun The M1939 (52-K) air-defense gun was efficient and well-proven, sporting a 55 calibre barrel. It had a muzzle velocity of 792 m/s (2,598 ft/s). General Vasiliy Grabin and General Fyodor Petrov directed the team responsible for the conversion, initially into an anti-tank gun. Soon it appeared ideally suited for a tank, and the first to use a derivative model, the D-5, was the SU-85, a tank destroyer based on the T-34 chassis. This was an interim measure as the gun had to be integrated on the T-34-85, but the time necessary in order to create the turret delayed its adoption. Other teams soon proposed the S-18 and the ZiS-53 for the same purposes. The three guns were tested at Gorokhoviesky Proving Grounds, near Gorkiy. The S-18 won the competition at first and its design was approved for use in the modified turret but dropped when it was apparent that it was not compatible with the D-5 mounting for which the turret was designed. However, the D-5, conceived by Petrov, was retested and showed a limited elevation and other minor defects, but equipped the first production series (model 1943) of the T-34-85 as the D-5T. At the same time, Grabin’s gun, the ZiS-53 showed mediocre ballistic performances and had to be reshaped by A. Savin. On December 15, 1943, this modified version, named the ZiS-S-53, was chosen to be produced en masse and equipped all T-34-85’s model 1944. Around 11,800 had been delivered during the next year only.

Rearview of a T-34-85, from Factory 174. Circular transmission access hatch, exhaust pipes, MDSh smoke canisters and extra fuel tanks can be seen. Turret: By choosing either the D-5T or the ZIS-85, guns with a very long barrel and without a muzzle brake, the recoil dictated a very large turret, or at least very long. This roomier design also had the advantage of being roomy enough for three crewmen, the commander being freed from having to load the gun. This, in turn, helped him concentrate on possible targets and generally to have a better awareness of the battlefield. The advantage of a three-man turret was already known by the British since the twenties, and the Germans found it very convenient for their main tanks, the Panzer III and IV. The advantages of such a configuration became obvious during the campaign in France. Having the commander free to focus on his tasks and excellent tank-to-tank communication gave them a clear-cut tactical superiority over the French, whose tanks mostly had one-man turrets. This new turret, ordered by The People’s Commissariat for the Armor Industry, was partly based on the T-43’s turret and was hurriedly adapted by Krasnoye Sormovo Factory chief engineer V. Kerichev. It was a compromise design with a slightly reduced base ring, two periscopes and the commander cupola relocated to the rear, for full peripheral vision. The radio was also relocated, allowing easier access, better signal and range. Other modifications Apart from the turret, the hull was almost unchanged except for the turret ring. It had to be enlarged from 1.425 m (56 in) to 1.6 m (63 in) to give a more stable and sturdy base, but this made the entire upper hull more fragile. The space between the huge turret and hull was also quite large and created natural shot traps. But the large hull supported quite well the added weight without excessive stress on the suspension and main body frames, a testimony to the ruggedness of the original design. Stability was not compromised, as trials at Kubinka showed. The hull was nonetheless reinforced and the turret frontal armour rose to 60 mm (23 in), like on the T-43. With an unchanged engine, transmission, gearbox and suspension, weight rose by only one ton (32 compared to 30.9 for the model 1943). Fuel capacity was augmented to 810 litres (215 gals), which gave a 360 km range (223 mi). However, since over time the weight continuously rose without any changes to the engine (the original T-34 model 1941 weighed just 26 tons), this lowered its top speed to just 54 km/h (32 mph). A clear gain appeared in terms of cost-efficiency. The new T-34-85 unit cost was 164,000 rubles, which was higher than that of the T-34/76 model 1943 (135,000), but still largely inferior to that of the model 1941 (270,000) and certainly far less than any completely new model would have cost. Production rose after the introduction of this new model, notably due to the opening of new lines in “Tankograd”. Since the hull parts of the model 1943 had been simplified, the new T-34-85 model 1943 inherited these, and deliveries rose to 1200 each month by May 1944, shortly before the launch of the most massive operation planned by the Stavka: Bagration.

T-34-85 models 1943 and 1944
The T-34-85 model 1943 set the general appearance for the series, which remained mostly unchanged until 1945. It had a cast turret and deflector strips were later welded to the front to cope with the shot trap effect. This caused a shell to bounce off the sloped front and ricochet into the lower front part of the turret. The mantlet was 90 mm (3.54 in) thick. Inside, the gunner was positioned to the left of the gun. Behind him sat the commander and the loader to the right. Behind the commander cupola, there were two smaller hemispheric cupolas, each pierced by five vision slits protected by bullet-proof glass. The early version was characterized by a two-piece hatch, while the 1944 version had a single piece one, opening to the rear. There were also two side pistol ports and vision slits above them. OI the later version, these were simplified and the vision slits eliminated. The loader had his own small hatch and two ventilators were located above the gun to extract fumes. The driver’s hatch had two vision slits and was his only access point into the tank. The late-model 1943 turret could be recognized by its almost centred commander cupola and large periscope. The early 1943 production version and the 1944 model both had the commander cupola shifted backwards. They differed in the shape and configuration of the exhaust ventilators and the larger breech-loading equipment of the gun. The gun itself was activated through pedals and a small wheel. The breech block could be manually or semi-automatically operated. The recoil was supported by a hydraulic buffer and two recuperators. Both the gun and the DT machine-guns were activated with triggers. The gun mounting itself was easy to remove after dismounting the mantlet, providing easy maintenance. Aiming was performed with a TSch 16 scope, which had a 16° field of view and 4x magnification, and TSh-16 and MK-4 sights. This was still a bit rough compared to German equivalents, but real improvement over previous systems. 35 rounds were carried (mostly AP with some HE), mostly stored on the turret floor and in the turret basket. Many model 1944s were also equipped with MDSh smoke emitters, placed at the rear of the hull near the exhausts. Trials also showed the tank had a tendency to pitch forward due to the increased weight of the turret. The first four vertical coil springs were reinforced accordingly. The model 1944 turret was made up of two massive cast pieces (top and bottom) welded together, with any other external and internal features barely changed. Only the length of the barrel and mounting could help distinguish them, as well as the turret top configuration. Most (late) model 1943’s had a periscope replacing the right ventilator, just in front of the commander cupola. The front hull was protected by 45 mm armour, sloped at 60° from the vertical, giving an effective frontal thickness of 90 mm (3.54 in), while the sides had 45 mm (1.77 in) at 90°, and the rear 45 mm (1.77 in) at 45°. The turret face and mantlet were 90 mm (3.54 in) thick, with 75 mm (2.95 in) sides and 52 mm (2.04 in) at the rear. The turret top and bottom were just 20 mm (0.78 in) thick. The drive-train comprised a double rear drive sprocket, a front double idler and five double road-wheels of various types. The early production vehicles were given rubberized ones, but because of shortages the model 1944 had metal-trimmed spoked models, which became the norm. These gave a rough ride, despite the Christie type huge vertical coil springs, which probably reached the very limits of their potential. The engine was almost unchanged since the first T-34, still, the reliable and very sturdy 38-litre water-cooled V-2-34 V12 diesel, which developed 520 hp @2000/2600 rpm, giving a 16.25 hp/ton ratio. It was coupled with the same old constant mesh all spur gear transmission (nearly obsolete), with 4 forward and 1 reverse gearsand steering by clutch brakes, which were a driver’s nightmare. The best average speed obtained in tests was 55 km/h (34.17 mph), but the usual cruise speed was around 47-50 km/h (29.2-31 mph) and the best possible off-road speed was around 30 km/h (18.64 mph). The T-34-85 was still quite mobile and agile, having a turning radius of about 7.7 m (25.26 ft). However, the range was somewhat reduced and consumption was around 1.7 to 2.7 km per gallon (1.1 to 1.7 miles per gallon) on a rough ride. The starter was electric as well as the turret traverse, served by 24 or 12-volts electrical systems.

A Polish T-34-85 in a museum Secondary armament comprised two DT 7.62 mm (0.3 in) machine-guns, one coaxial, which could fire tracing bullets, and one in the hull, shooting through a ball mount protected by a heavy hemispherical shield. Ammo comprised between 1900 and 2700 rounds. The main gun could fire either APBC, APHE, HVAP and simplified AP rounds. The model 1943 was equipped exclusively with the original D-5T gun, while the model 1944 adopted the modified ZIS-S-53 (S for Savin). However, late models 1in 944 also adopted the improved model 1944 D-5T, whose development never stopped. It was capable of piercing 120 mm (4.7 inches) at 91 m (100 yards) or 90 mm at 915 m (1000 yards), placed at a 30° angle. The usual round weighed 9.8 kg and muzzle velocity on average was 780 m/s (2559 ft/s). The 85 mm ZIS-S-53 L54.6 introduced on the model 1944 had slightly improved performances. The original D-5T barrel was 8.15 m (26.7 ft, L52) in length and had a higher muzzle velocity, but the 85 mm ZIS-S-53 model 1944 was less complicated to manufacture. The elevation was kept unchanged at -5° to +20°. The early model 1943 had a hull -ounted radio which was later relocated into the turret. Manufacturers of the model 1943 comprised Factory N°183 Ural Rail-Car Factory (UVZ), Factory N°112 Red Sormovo Works (Gorki) and Factory N°174. Together they produced most of the model 1943 tanks. The first ones were delivered in December 1943 and immediately given to one of the elite Tank Guards battalions. Production of the early model 1943 was around 283, while 600 model 1943’s and 8,000-9,000 of the model 1944 were delivered in 1944, and between 7,300 and 12,000 model s1944’s left the factory lines in 1945. It seems that a total of around 17,680 model 1944’s were built between March 1944 and May 1945.

Variants
Besides the SU-100, which was built using the T-34-85 model 1944 chassis, other common variants of the T-34-85 were: – The flame-thrower OT-34-85, mounting an AT-42 flame-thrower replacing the coaxial DT machine-gun, with a range of 80-100 m. – The PT-3 mineroller, the mine removal version, a device which comprised of two rollers suspended under a pair of arms, protruding 5 meters in front of the hull. Each engineer regiment was comprised of 22 regular T-34’s alongside 18 PT-3’s (from “Protivominniy Trail”/counter-mine trawl). The engineers also used bridge-layer and mobile crane conversions of the chassis.

The T-34-85 in Action
When the first T-34-85’s delivered by Zavod #112 appeared, they were given to the best units, the elite Red Guards battalions. However, they were in training during December 1943, so it is uncertain whether they saw action before January or February 1944. By then, around 400 had already been delivered to front-line units and instantly became popular with the crews. They gradually replaced the T-34/76 and in mid-1944 the T-34-85 outnumbered the older versions. By then they formed the bulk of the tank units on the eve of Operation Bagration, the Soviet response to the Allied landings in Normandy, and the biggest offensive ever planned by the Red Army to date. This was the final push, aimed at Berlin. Before the production built-up, the T-34-85 model 1943 were usually given to chosen crews, usually of the Guard units.

A propaganda shot showing infantry dismounting from a T-34-85 – Credits: Flames of War The T-34-85 took part in all subsequent engagements with the rarefying Panzer divisions, encountering a mix of Panzer IVs Ausf.G, H or J, Panthers, Tigers and many tank-hunters. There was no starker contrast than between the nimble and low Hetzer and the Russian model, towering relatively high above the ground. It was certainly not the tallest in use, the Sherman being taller, but the broad turret still made a relatively easy target when seen from the side, adding to the fact it was less sloped than the hull sides. Finishing was still rough and quality had deteriorated due to the lack of skilled manpower. Reliability, however, kept pace with their intensive use. They were still easy prey for many German tanks of the time, just like the previous T-34/76, but the high-velocity and range of the 85 mm (3.35 in) were clearly an advantage in many engagements. It scored kills at ranges of 1100-1200 m (3610-3940 ft), although better optical equipment and training would have probably increased this figure. ThesizeS and DT were not really used at their full potential due to crew's habits and tactical doctrine that still advocated trading range for penetrating power.

Captured T-34-85 – Credits: Beutepanzer By late 1944, when entering formerly occupied East European countries and Eastern Prussia, T-34-85 tank crews faced a new threat. This did not come from German tanks (although the Königstiger and many late tank hunters were quite impressive, if few in numbers), but from the average infantryman, even from citizen militias (Volksstrurm) armed with the Panzerfaust, the first shaped-charge launcher. To deal with this sneaky and effective weapon, the Russian crews took the matter in their own hands. They mounted makeshift protections made of bed frames welded on the turret and hull sides, but far enough from the hull itself to make the charge detonate sooner and spewing its hig- pressure metal jet harmlessly on the surface.

Sources:

anks-encyclopedia.com/ww2/soviet/soviet_T34-85.php