Certain tanks seems to have buggy or wrong armour values around the turret and gun mantlet. Notably those that I've found are the M103 heavy tank, M48, M60 Patton. These 3 can have the turret destroyed by just ~70mm of pen from the M4A3 Sherman gun by aiming around the mantlets of the tanks, penetration shows up as green and turret can be destroyed.

The Object 777 can also be easily destroyed by firing from a slight angle(777 downhill) with just about 100mm of pen from the Panther's 75mm gun. Aim for the square piece above the gun mantlet. (This could be normal, the 777 seems to have a weird armour layout according to WOT values)

The various IS3 can have their turrets destroyed by going through the gun mantlet with ~150mm of pen from the Panther's gun as well. The vanilla MOW IS3 does not have this same issue.

The Lowe also has this issue, the mantlet doesnt seem to have a hitbox and any shots going to the mantlet pens the turret with just 150mm of penetration.

Non exhaustive list, just some of the more notable fragile heavies that I've seen. Im just going by WOT/Default MOW values so if its intended behaviour do correct this. No other mods running and tested in the editor.