Large Caliber High Explosive....

[Djuice]

It's been documented in WW2 that Soviet assault guns like the SU-152 and ISU-152 were sometimes used as heavy TDs. It's been reported that 152mm HE rounds were capable of defeating German heavy tanks quite reliably, due to the sheer kinectic and explosive energy of the 152mm HE round. Even if it did not penetrate the armor of said tank, it would of done considerable amount of external damage, not to mention lethal amount of spalling inside the vehicle.

Yet in SPWW2 it doesn't seem so, I've used a ISU-152(Unit 746) against a Panzer IV(h)(Unit 036), I fired 20 HE rounds @ about 1,000m (20 hexes), about 12 hits, scoring sometimes 4 pen, but most of the time 0 pen, and I did score once 6 pen on it's hull which unfortunately wasn't able to take it out.

Is the game suppose to assume that HE rounds from large caliber guns ineffective against armored targets? If so is there some way to rectify it?