Generally you'll want to shoot at things that have a green penetration notice (center of cross-hair changes colors). If you are loading HE you might be able to still deal damage even if it is red, however the amount of damage you'll do will really drop if you hit a red patch compared to a green patch at the same angle.
- Top/Bottom of the chassis
- Rear of the chassis
- Sides of the chassis
- Lower Glacis (the bottom part of a tanks front)
- Commander Hatches (Those things on the tops of turrets where a tank crew can poke their heads out of)
- Driver port / machine gun port in the chassis
Now you'll notice a lot of times you'll hit something that shows green (penetrable) however you'll bounce or fail to penetrate the armor. This is because armor becomes more effective when it is angled. Armor at a 60 degree angle has about double the effectiveness so 100mm becomes around 200mm. There is also spaced armor that will cut down your rounds penetration effectiveness by a lot because of how shells work in the dead space.
Now for this area I'll go into a few different tanks on specific spots and the kind of gun needed to deal damage. This is based on shooting the tanks front which is generally what direction they'll be pointing towards you.
- Super Pershing (the hatch under the two barrels on the top of the turret)(top half of the hull with gold IS-3)
- KV-5 (the R2D2 which is the larger cylinder that is poking out of the chassis)
- Maus / E-100 (Gold rounds to the turret's from when they are looking directly at you with an IS-3+)(Lower glacies, the maus is harder because it is very small between the track's space armor)
- T-95 (Pretty dangerous, only those hatches at the top are reliable since the tracks can cover up a lot of that lower plate)
- IS-6 (For anything as weak as an IS-6's pen, shoot the top of the turret, the chance of bouncing on the chassis is too high)
- IS-3 (The very top of the turret there is a bolted on plate between the hatches and the gun which is extremely weak)
- T28 Prot (Gold rounds in the IS-6 can penetrate the center of the chassis where the clan tag is
And finally some spots to not shoot or be careful of shooting
- The T69 has a very bouncy turret if you use a low pen gun
- Anything sitting on the sides of tanks like gas tanks or the two things poking out of a T29's turret has no damage boxes so you'll be just shooting dead air.