According to War Thunder’s data, Jumbo’s APCR has 135mm penetration in 100m. But in Enlisted, it even hard to penetrate 4H’s hull. APCR should have high penetration and low effect after breakdown. But this APCR has low penetration and low effect, which means it is totally a piece of ****.
Honestly APCR is bugged/broken in war thunder as well, and Enlisted uses a really old version of WT’s damage models. There will probably never be a fix.
I’d rather just get the APCR removed so there’s more ammo for HE and regular AP, which is more than enough to fight the majority of the Pz IV’s, III’s and Puma’s you face. Not being able to frontally pen Panthers and Tiger’s is fine, the Jumbo would be way too OP if it was frontally impervious to every tank + able to frontally kill every tank (you can always flank and kill anyways). I use the Jumbo and I think it’s already pretty OP as is.
Actually I want the Jumbo to have the 105mm howitzer low pen high explosive. It would also differentiate it more.
I also think a normal campaign Jumbo with a 76MM would be a good equivalent to the Tiger it would have slightly more armor but a slightly less powerful gun.