FV215 Heavy Tank Destroyer: IS-3 Killer

Author: Mark Nash
Site: Tanks-Encyclopedia

The IS Killer That Never Was

After witnessing the debut of the Soviet IS-3 heavy tank at the end of WWII, the western armies were, safe to say, a little bit worried. As such the British immediately began work on new vehicles that could combat this new threat. In 1950, work began on the FV215. This was a little known British tank-destroyer project that never left the conceptual phase. It was set to be an IS killer, and would no doubt have sent a very cold shiver down the spine of Soviet tank crews.

This vehicle is known by many names, FV215 Heavy Anti-Tank SP No.2, Gun Tank No.2, or simply FV215. The design phase began November 1950 after a meeting was held by the War Office to determine just what vehicle would be suitable to carry the new QF 183 mm (7.2 in) L4 cannon. Morris were first to be given charge over development, but this was later handed over to Vickers-Armstrong.


The design team chose to base the vehicle on the chassis of the FV200. The chassis underwent minimal modifications, the largest change being the repositioning of the turret to the rear of the vehicle. This was to avoid the extremely large main armament hanging over the bow too far. The driver also remained at the front right of the tank.

A small scale mock-up of the vehicle. Photo: – Courtesy of Ed Francis

This image displays the Commanders position inside the mock-up turret. Photo: – Courtesy of Ed Francis

The large box-like turret mounting the 183 mm (7.2 in) main armament, in theory, had a full 360 Degrees of traverse, but this was not recommended on sloping services. It was commonly believed that the turret could only traverse 90 Degrees left and right. Despite its large size, there was still not enough room inside the turret for a working loading mechanism. As such, the predicted 6 rounds per minute would have been a hopeless fantasy. It is expected that this vehicle would need 2 loaders to service the weapon, but even so, the desired loading time would likely have gone un-reached. The vehicle had a meager load out, also likely due to space constraints, carrying only 20 separately loading rounds. The combined weight of charge and projectile was 104.8 kg. Not an easy task for the two loaders.

Defensive armament consisted of a machine gun of unknown caliber, most likely a .30 cal (7.62 mm) machine-gun. It was mounted in a small structure on the forward right of the turret roof. It was able to aim up and down a few degrees. There was also one .50 cal (12.7 mm) M2HB on an AA mounting above the commander’s hatch, on the right rear of the turret.

A Rare photo of the forward deck of the FV215. Photo: – Courtesy of Ed Francis

The armor thicknesses of the vehicle changed throughout its development. As it was intended as a relatively long range vehicle, its reliance on armor would have been minimal. None the less, it was given similar armor properties to the Conqueror. The upper plate varied from 125 to 152 mm (4.92 – 6 in) thick. The sides plates were 50 mm (1.97 in) thick, with spaced armor in front. The turret had the thickest armor on its front. It was 254 mm (10 inches) thick.

The vehicle was designed to be powered by an 810 hp Meteor Mk.12 engine. This would’ve propelled the 65-ton vehicle to 32 km/h (20 mph).

FV215 Heavy Gun Tank

Dimensions  N/A
Total weight 65 tons
Crew 5 (driver, gunner, commander, x2 loaders)
Propulsion 810 hp Meteor Mk.12
Speed (road) 31.7 Kph ( mph)
Armament QF 183mm L4 Tank Gun
.30 Cal. machine gun.
.50 M2HB Machine gun.
Armor 125 to 152 mm (0.79-3.07 in) hull front, 50mm (1.9 in) sides, 254 mm (10 inches) thick on the turret face.
The mockup of the FV215, showing the monstrous cannon. This stage is as far as the FV215 project got. Source: warspot.ru
The mockup of the FV215, showing the monstrous cannon. This stage is as far as the FV215 project got. Source: warspot.ru

The QF 183mm L4

In 1950 work started on the QF 183 mm (7.2 in) L4 gun. At the time it was the largest and most powerful tank gun in the world. The cannon was based on the 183 mm BL 7.2 inch howitzer, a WWI era weapon. The gun itself weighed a mighty 4 tons, and when fired produced 87 tons worth of recoil force. A shell of this size would understandably produce a substantial amount of fumes and smoke inside of the fighting compartment. As such, a large fume extractor was added to the barrel, a relatively new feature at the time.

One of the Ammunition stowage areas inside the mock-up turret, the scale of the Shell can be apreciate from the size of the cut-out. Photo: – Courtesy of Ed Francis

The L4 was designed to be chambered for only one type of ammunition, HESH (High Explosive Squashed Head). One can only imagine the devastation an explosive shell of this size would cause to a hostile vehicle. Whether the shell penetrated or not, the concussive force of such and explosion on the crew inside would be deadly in its own right.

The 183mm was tested in live fire trials against a Centurion and a Conqueror. In 2 shots, the 183 blew the turret clean off the Centurion, and split the mantlet of the Conqueror in half.


Alas, the FV215 project never came to be. The Morris company was the first to be tasked with building a full-scale model, followed by two prototypes, one to test mobility, and for armor testing. In June 1954, Vickers-Armstrong became the owners of the contract and were given the same task.

A face on photograph of the smaller scale mock-up with gun elevated. Photo: – Courtesy of Ed Francis

January 1957 marked the end of the road for the SPG, even though the requested scale model was finished, and 80% of the blueprints were ready and waiting for further development. The intended role of the vehicle had been over taken by increasing development of ATGMs (Anti-Tank Guided Missiles). These granted the same, if not better, anti-armor capabilities, with the experiments ultimately culminating in the Malkara and Orange William missile systems.

The only 183mm armed vehicles to reach prototype phase were the FV4005 Stage I and Stage II. Both vehicles were based on the Centurion MBT. The Stage I featured an exposed gun with an automatic loading system, on a limited traverse ring. The Stage II featured a fully enclosed turret, with a full 360-degree traverse. As the loading system wouldn’t fit in the turret, it was removed.

Just one vehicle was used for both prototypes. The Stage II now sits outside the Tank Museum in Bovington.

Busting a Myth, The FV215b

This vehicle has showcased in Wargamming’s “World of Tanks” for quite some time now, but it is almost certainly a fake vehicle. It is a FV215 with a rear mounted Conqueror turret and the 120 mm L1A1 gun.

The vehicle was thought to have come into existence because of a confusion with the designation FV215 heavy gun tank. It was interpreted as a second separate project but was, in fact, one and the same. Even the designation of FV215b is somewhat of a misnomer.

A blueprint of the FV215 from the 1950s. Source: warspot.ru
A blueprint of the FV215 from the 1950s. Source: warspot.ru

Links & Resources

The Heavy Gun Tank on warspot.ru (Russian).
English translation of the above.