Frontally the IS-7’s armor has both very thick places and heavily angles places that give it a very tough frontal armor scheme. Like most tanks the main weak spot is the lower frontal glacis (LFG) and there are also some weaker parts near the mantler on the frontal turret armor(FT #1 / FT #2). However, the driver’s port located under the gun is deceivingly strong and the commander hatches(the yellow strip on the first image and more specifically the second frontal image) are also designed to fool you. Looking at the IS-7 the left commander hatch(A3-A5) is tougher than almost any other commander hatch you will find and also has a gigantic view port on it that takes no HP damage. The right commander’s hatch on top(A6-A7) only takes damage if you shoot the small “lip” behind it unless if you are shooting directly down from above. These two spots are not very apparent but are your best choice if you are stuck shooting at an IS-7 that is very close to you. The actual hull armor is very tough aside from the obvious lower frontal glacis(LFG) weak spot. The upper glacis’ are all heavily angled and while they are only 150mm thick are extremely strong due to the angles. If you are able to negate the angles by shooting down while close/above an IS-7 they become a better option than the LFG. The driver’s hatch in A1/A2 is very strong as well since it’s angle actually increases when compared to the glacis plates around it.
Usually IS-7 drivers do not angle since their armor scheme focuses on keeping the frontal armor pointed directly at their opponent. This keeps those compound angles on the frontal armor and thus makes the IS-7 difficult to damage aside from the lower glacis. If however an IS-7 driver actually does decide to angle then you should still stick to either the lower frontal glacis or if they angle heavily switch over the lower side armor. The ammo racks are located just behind the driver(under the front of the turret) and behind USH #1. Aim here and make them regret angling.