Ok Bellator your right, its those ~350 meters after i did a lot of research at this pages:
http://www.lonesentry.com/manuals/90...ion/index.html
http://www.panzerworld.net/armourcalculator
I was really confused by wikipedia ( possibly propaganda or fake info with those "2400" meters

)
But in all cases, you can not penetrate that lower hull at all, because its bugged as wiki site...
BTW this game needs a really big patch about armor/armor penetration corrections though.
But in extream battle conditions where the slope angle was negated with ground/terain inequality it could be far more meters not just 350m... That slope did great work on that final armor value as well...
There are many factors which gives no sence at all...
Like this for example:
Panther`s 80mm upper hull plate @ 55 degrees vertical can be penetrated from 800 yards...
60mm!!! lower hull plate @55 degrees vertical only from 600 yards WTF ???