Vehicle Ammunition Confusion

[Brown Sugar Cinnamon]

So I'm confused by how shell types work in this game. Does the type of shell a Tank/IFV change based on its target?

For example, the M1A1 Abrams is listed as having "High Explosive" & "Kinetic", so my assumption would be that if targeting a tank it uses kinetic and inf use high explosive. If that is the case, does the listed "HE" value only matter for shooting at soft targets? Or does that value also indicate how strong the shell is against tanks when penetrating?

I've also seen tanks with "High Explosive Anti Tank" shells but these appear to have the same HE values, just a lower AP value. So I'm guessing these shells don't do any more damage but just have their AP on contact calculated different per the in-game tool tip? If so, that just seems odd since my very basic understanding is that these type of shells would do more damage that a completely kinetic shell.

Last thing that i'm confused about is IFV auto-cannons vs armored targets. For example, the Bradly has a listed AP value of 4 but when I attempt to target a tank, it just won't shoot. Is that because it knows it won't pen? If so, if it gets chance at a side or back shot on a tank like a T80, would it take that shot? Or is there just no shooting at tanks at all for these types of guns?

Sorry for the short novel, I really love the game and I'm trying to understand the smaller details. Thanks for any help

[Brown Sugar Cinnamon]

TLDR: How to tell what tank shells actually do and can IFVs shoot tanks with their autocannon?

[Urk_da_WAAAGH!]

(penetration - armor) / 2 + 1 = damage

penetration value of kinetic rounds is increased by +1 every 175 meters under the max range

For related questions visit WarYes damage calculator

[themediocrity]

Your impressions here are correct. HE damage on tank cannons is only against infantry. Only note is that HEAT is just a different kind of AP which has no penetration change with range and always does a minimum of 1 damage regardless of target armor.

[CORRIDA]

The tank ammunition is somehow strange, as if they only have 3 weapon slots per unit and there is no other way. I assume this wasn't done on purpose like in SD2 because otherwise tanks would be too strong.