The silliest unbuilt project

[Orionblamblam]

I drew better tanks in the 4th grade.

Sober?

Yeah. Nevertheless, my tank designs in the 4th grade still kinda sucked.

My 6th grade tanks though...

 

[Conspirator]

i always thought that KV-1s and KV-2s were a bit unrealistic and were just a tank project until i learned more. then i saw the proposal for the KV-4 and it was actually pretty cool. sloped armour lower profile and better weight distribution than the previous fridge-headed models. but just thinking about loading a KV-2 and slamming a HEAT round through a tiger II is a very tempting thought.

The KV-220s though....
wasnt there a KV-220 pillbox?

 

[Nik]

Thing about Pycrete, IIRC, was that it would work. Well, 'kinda, sorta'. Frozen 'paper mache' turned out to be remarkably resilient to gun-fire and, yes, thawing...

Thankfully, 'escort carriers' came along, so semi-kamikase 'HurriCats' were no longer required, and Pycrete's inventor faded from history...

 

[Bottleship]

i always thought that KV-1s and KV-2s were a bit unrealistic and were just a tank project until i learned more. then i saw the proposal for the KV-4 and it was actually pretty cool. sloped armour lower profile and better weight distribution than the previous fridge-headed models. but just thinking about loading a KV-2 and slamming a HEAT round through a tiger II is a very tempting thought.

Theoretically it is possible. The M-10 howitzer (used in the KV-2) could fire HEAT with a 250 mm AP, but by the time 152 mm HEAT appeared in the Soviet army, only a few KV-2s had survived. But, getting from KV-2 to Tiger would be very difficult.
By the way, the KV-2 was not the only tank with howitzers. The KV-1S (light version of the KV-1) in the project had options with an 85 mm cannon, 122 mm and 152 mm howitzers, in fact, it turned out to be possible to create a tank with a 152 mm howitzer in a turret the size of a KV-1 turret, however, it would be pretty cramped. It was also a 152mm howitzer with 508 mps. There were several projects of the T-39 heavy tank, which had a 152-mm NG howitzer (German development for the USSR, sFH 18 "sister") with 542 mps, in another version the T-39 should have been armed with a 152-mm cannon 1910/1930 with 660 mps ... In 1942, the project of the IS tank was discussed with a 152 mm ML-20 with 660 mps (imagine a giant T-34 with a turret similar to the SU-152). Even larger was the T-100V project with a 203 mm B-4 with 607 mps, as well as a VL with a 305 mm B-23 with 638 mps. This is probably the largest howitzer the Russians wanted to put in a tank turret. Apart from a few projects similar to the German Waffentrager, for example, the T-34 with a 400 mm howitzer ("mortar" according to Russian classification, the same base made it possible to install a 305 mm howitzer or a 210 mm cannon):

A pillbox with a KV-220 turret supposedly existed, but there are doubts about the reliability of the only photo:

In any case, the KV-220 really existed:

 

[Conspirator]

seems to me like they just wanted to build the biggest gun toting tank possible to scare the sheet out of the Germans. 155-200mm would be sufficient enough to battle them. you dont need to go through all the way to 300-400mm howitzers. and besides. can the hull even withstand the recoil of a 350-400mm howitzer shot without structural reinforcements?

 

[Rhinocrates]

Probably the two silliest PAVs I can find. One is the AirspaceX MOBi, here because of unnecessary origami, while the lava lamp in a sombrero is an AirVinci.