IS-6 is one of those tanks you want to get rid of fast regardless of the players skill even if it has sort of a weak gun for the levels it’s usually matched to. It’s armor is quite good which warrants learning as much as you can about it’s weak spots to be able to penetrate it well.
From the front you should try to shoot the IS-6 right down the middle below the gun to hit the driver, but you have to be able to penetrate at least 100mm of armor on the hull, while the turret has 150mm armor.
The sides of the turret house the crew in the front and the ammo rack in the back of both sides of the turret. There’s also a thin strip of weak armor on the back of the hull where the engine is located
The whole back of the turret houses the ammo rack and the middle of the hull houses the engine.
The ammo rack is located on the back side of the IS-6’s turret.