T-100Z | The KV-2 That Never Was

GetGæijined · November 1, 2025, 7:10am

Intro:
I have been enjoying researching rare Soviet monstrosities, and this one has had next to no mentions on this forum yet, despite looking like a super fun and unique vehicle. So today I present to you: the T-100Z!

History
The history of the base T-100 is pretty wel known at this point, but I’ll quickly recap for those unaware:

During the Winter War it became apparent the T-35 heavy tank was already becoming outdated, and the Red Army needed a new heavy ‘break-through’ tank. And so, three prototypes were created, the SMK (which we already have in game ofcourse), the T-100, and the KV. The T-100 was very similair to the SMK, also having a long body with 2 turrets, one with a 45mm gun and one with a 76mm. All three prototypes were field-tested in Finland, where the KV tank came out as the most reliable tank, and it went on to create the entire KV lineage. The SMK was sadly scraped, and the T-100 was converted into a self propeled gun which we know as the SU-100Y, which we also already have in-game. The SU-100Y was used in the defence of Moscow, and still survives in the Kubinka Tank Museum today.

If you want to know more about the T-100’s history, the user OddPhenomena has a way more detailed post on the regular T-100.

This is the story how most people know it, but before the full implementation of the KV series, Army Commander 1st grade G. Kulik already requested a design for a heavy tank armed with the M-10 152mm howitzer. A new project was started at the Leningrad Plant No. 185 under the leadership of L. S. Troyanov, which sought to place this howitzer in a new turret that could be mounted on the already existing T-100 prototype, named the T-100Z. One fully operational turret would be produced in 1940, but at this time the existing T-100 was already converted to the SU-100Y, and with the KV-1 and KV-2 now officially in use, the T-100Z project was stoped immediately. The produced turret would be used in action however! It was turned into a pillbox and used in the defence of Leningrad in 1941. It’s fate after this is unknown.

Translation text in photo: “Tank converted into a pillbox. Photo by our special photo correspondent A. Kapustyansky.”

This Vehicle’s Place in the Game
Let’s get the elephant out of the room, this vehicle was technically never built. The turret which makes this vehicle unique was never mounted on the hull it was supposed to. But the entire turret was build and was fully functional, and even used in combat. The hull was also completed and functional, and used in combat as well, as the base T-100 and the SU-100Y. Nearly every component of this vehicle was made, many of which specialized, so according to Gaijin’s rules, this vehicle should be more then qualified to be added into the game.

Now for the game itself. I believe a Battle-Rating of 3.7-4.0 is appropriate. It’s effectively a KV-2 that’s slower, larger, and with less armour, but you get an additional 45mm gun and more crew. This would be a perfect event vehicle, being fun but not that competitive. This would also be a great chance for people to get a unique 152mm vehicle, as the KV-2 Model 1940 hasn’t been available for quite some time apart from randomized lootcrates.

Specifications
Armor: 60mm on all sides, 20mm on the floor and roof.
-The base T-100 hull remains functionally untouched. The turret was designed to fit, and the only thing that would have to be adjusted is the 76mm shell racks being replaced with 152mm racks.
-Specifications on the armor if the turret I could not find, and it’s hard to tell with the available pictures (Visible armor thicknesses can often be deceiving, they may look a lot thinner because 1. it’s hard to get a true sense of the scale, and 2. the plate thicknes may continue on the inside as you often see on other designs, so that plates properly align and lock together.) I believe it’s pretty safe to assume this turret is armored with 60mm all-round as well, just like the rest of the vehicle, with 20mm on the floor and 20-30mm on the turret roof. My reasoning for this is the fact that the turret was tailor-made for the existing T-100 which also has 60mm all-round, with 20mm on the floor, and 30mm on the roof of the 76mm turret. But yet again, I could not find any proper sources, so right now the only source I have is “trust me bro”.
Weight: 64 tons
Engine: 850 hp Mikulin GAM-34BT V-12 petrol @ 1850rpm
Transmission: 4 gears forwards, 1 gear reverse
-Transmission and engine are the same as the T-100/SU-100Y
Speed: ~32 kph, 4.1kph reverse
-The SU-100Y in-game weighs 64 tons as well, so I believe the T-100Z would have comparible mobility.
Crew: 7
-Driver
-Assistent driver
-Gunner (45mm)
-Loader (45mm)
-Commander
-Gunner (76mm)
-Loader (76mm)
-The crew-layout should be the exact same for the T-100Z as on the regular T-100.

Armaments:
*7.62mm DT Machine gun
-Coaxially to the 45mm

*20-K 45mm
Reload: 3.8 seconds, 2.9 seconds Aced
Ammunition:
*BR-240SP
-APBC, 1.43kg, 757m/s, 73mm Max penetration
*BR-240
-APHEBC, 1.43kg, 29.26g filler, 760m/s, 70mm Max penetration
*O-240
-HE, 2.14kg, 118g filler, 335m/s, 4mm penetration
*BR-240P
-APCR, 0.85kg, 985m/s, 94mm Max penetration

*M-10 152mm Howitzer
-Slightly earlier version of the M-10T the KV-2 uses, both are functionally identical
Reload: 1-1,5 rpm, or 60-40 Seconds
Ammunition:
*G-530
-Anti-Concrete (SAPCBC), 40kg, 5.1kg filler, 530m/s, 69mm Max penetration
*PB-35
-Anti-Concrete (SAPCBC), 51,06kg, 4.85kg filler, 436m/s, 86mm Max penetration
*OF-530
-HE, 40kg, 5.82kg filler, 530m/s, 48mm penetration

Both the 20-K and M-10 are guns that already exist in-game, so that part is easy. There are 393 pieces of 45mm ammo, all placed around the 45mm turret. The 152 ammo is a bit trickier, as these were never fitted into the actual T-100, so the 76mm racks would have to be adjusted. But considering there’s place for 120 rounds of 76mm shells throughout the entire main-turret fighting compartment, I think there’s certainly place for around 20-30 152mm shells, which is realistically all you’re going to need in a battle. It should also be noted that the reload of the M-10 gun will likely be slower than that of the KV-2, as there’s only 1 loader feeding the gun.

Conclusion
I believe this is a truly unique vehicle that doesn’t really get the light of day it deserves. Hopefully with this thing being added this could change, but we’ll have to see.
The 2 pictures shown previously are the only ones we have of the unique turret sadly, but below I’ll leave some drawings and blueprints, as well as pictures of the regular T-100, and models of the T-100Z to show what it would look like. All My sources are down there as well. Let me know what you think of this beauty of a tank, and God bless!

Pictures:

Spoiler

Translation text in photo: “This is what the T-100-Z tank with a 152 mm howitzer should have looked like. Scale 1:35.”

Blueprint of the T-100, components in order:
1: Suspension tensioning mechanism
2: Driver’s port
3: 45 mm 20-K
4: 45 mm turret commander / gunner’s seat
5: 76 mm L-11
6: 76 mm turret commander’s seat
7: 76 mm turret gunner’s seat
8: Commander’s machine gun
9: Side firing port
10: Drum ammunition rack
11: Rear firing port
12: Turret 76 mm ammunition stowage
13: 76 mm loader’s seat
14: Engine
15: Cooling system fan
16: Exhaust pipe
17: Transmission access hatch
18: Drive wheel
19: Side clutch
20: Engine sub-frame
21: Support roller
22: Fuel tank
23: Floor 76 mm ammunition storage
24: Emergency escape hatch
25: Fuel tank filler tube
26: 45 mm ammunition rack
27: Machine gun ammunition
28: Driver’s seat
29: Guide wheel
(Credit: OddPhenomena)