- Yes
- No
Today I would like to suggest a prototype SPG with a very large gun and a very large chassis based on the T-28: The SU-14, in one of its original configurations.
(Note: A later version of this vehicle, the SU-14-1 (1940) has already been suggested. The vehicle in this suggestion is an earlier version based on a different chassis, with a different gun and without the armored superstructure.)
History:
Spoiler
The initial version of the SU-14 was designed in 1932 by Spetsmashtrest, following a request in September of 1931 to create a chassis that could carry a “triplex” of heavy guns, meaning it could choose to mount a 152mm gun, a 203mm howitzer, or a 305mm mortar. The desired 152mm gun and 305mm mortar were not ready at the time though, so the vehicle was developed with the 203mm B-4 howitzer as its armament. You might know this artillery piece as being based on the T-35, but actually, this initial version (SU-14) was based on a modified T-28 chassis. The modified chassis had the engine in the front and used some parts from the T-35, including elements of the suspension, which is why the suspension might make this look more like it’s based on a T-35 than a T-28. A later version of this would be based on the T-35 chassis, but this particular version is based on a T-28.
Unfortunately, the choice to base this SPG on the T-28 would cause problems. Technically, the first example would be ready by May 1934, but transmission problems from the T-28 meant it had to be modified until July 1934. After this it underwent firing trials, but its tracks were damaged during transport and the engine overheated, so driving trials couldn’t even be done at this time and had to be postponed. The rate of fire was low, as the 203mm shells were heavy and needed to be awkwardly loaded with cranes, and its loading system was unreliable. This initial version used a low-power barrel. Despite the large chassis, the recoil of the gun would still cause the vehicle to sway and the crew would have to hold on to the handrails tightly to stay on.
After this, the SU-14 received reinforced tracks and an improved cooling system. This meant that its next set of trials, it was able to be driven, but the gearbox would break after driving 34 km. The barrel was also changed to a high-power barrel, and the gun was tested at extreme angles.
In 1935, the SU-14 was modified to use the main clutch and gearbox from the T-35. During its 1935 trials, the SU-14 was able to drive 500 km and even demonstrated good driving performance. (This is also why I suggest the 1935 version, as it had the most successful driving performance of the early SU-14 model.) On top of the previous issues with the gun, particularly loading, more issues were discovered at this trial. Ball mounts were provided to fire DT machine guns from, but it was found it was impossible to use them. Furthermore, it was also found that the gun body could make it hard to use the stored ammunition for the main gun. With all these flaws, it was decided to create a new modification of the SU-14. This new version would be called the SU-14-1, and would be based on the T-35 chassis instead of the T-28. The T-35-based SU-14-1 looks very similar to the T-28-based SU-14, but it is not identical. One of the easiest ways to tell the difference between them in photos is that the SU-14 has rectangular holes on the side, while the SU-14-1 has circular holes on the side.
Interestingly, although the SU-14-1 was intended to replace the SU-14 due to its flaws, a couple developments would be continued with the original SU-14 anyway. In 1937, it would receive a 152mm B-30 gun, and in 1940, it would receive an armored casemate like the later version of the SU-14-1. Both the SU-14 and SU-14-1 would be used in defense of Moscow in 1941 in their latest forms.
Specifications:
Spoiler
Armor: 10-20mm
Crew: 7
Weight: 48 tons
Armament: 203.2mm B-4 Howitzer (8 rounds stored in the vehicle)
3x DT machine gun, to be used in 6 mounts in the sides of vehicle (may not be usable, as it was found the mounts couldn’t be used in testing)
1x DT machine gun in an anti-air mount
(2268 rounds of DT ammunition stored in the vehicle)
Engine: M-17 V12, 500 hp
Top speed: 27.2 kph
Fire rate: 1 shot per 5-7 minutes (this would very likely be adjusted in game for balance purposes)
For the gun, the information is a little less clear, but it seems it had a maximum range of 18 km and a muzzle velocity of 606 m/s. It had access to HE shells and the shells weighed 220 lbs.
Photos:
Spoiler
The SU-14 would be a beastly SPG with a massive size and massive gun. The armor is not very impressive, though, and the top of the vehicle is exposed, so you will need to be very careful about avoiding hits. The spacing of the tank might mean you could survive some shots, but that doesn’t mean much when the crew would be vulnerable to machine gun fire. With the similarly massive gun, shell weight, and muzzle velocity, the SU-14 would likely have a similar armament to the M55 SPH, but the crew above would not be protected and the mobility would be much worse. It’s likely this would be a lower BR the M55. The ammunition capacity is also lacking, but you probably don’t have to worry about that too much because of the long reload. This behemoth is mostly about the gun, and maybe the size of the vehicle as well. This vehicle would give the Soviet tree a huge caliber monster artillery piece for low to mid rank.
Thank you for reading my suggestion.
Sources:
Spoiler
https://www.globalsecurity.org/military/world/russia/su-14.htm
Heavy self-propelled SU-14
SU-14 SPG: Soviet Firepower Unleashed in the 1930s
Tank Archives: SU-14 Initial Trials
Triplex TAON, SU-14
B-4 (Model 1931) 203mm Self-Propelled Heavy Howitzer / Towed Artillery (Howitzer info)
203 mm Howitzer M1931 (B-4) Field Gun | World War II Database (Howitzer info)