YT channel with penetration simulations

[Imp]

The truth is especially nowadays you have no real idea what the armour is. They can be fitted with all sorts of different armour packages when fielded or makeshift addons like rubber sheeting. Same goes for WWII you hit a jerry can or something attached outside. Poor armour subject to starring & shattering.

Plus if you go to that detail you would need to rework every gun. Penetration will fall off at different rates due to muzzle velocity, covered partly I assume by max range.
HEAT should be less accurate at range vs moving targets due to flight times etc.

Its good enough its not a simulation but it does a good job of conveying the right feel.