Hello,
I searched the forum to see if this was asked already, and I could not find it, so here goes:
Armor-piercing ammunition, usable with standard IS autocannons and light IS autocannons, allows all hits a chance for a critical hit against BattleMechs, and improves the chances for a critical hit against Combat Vehicles, per TW, p. 140, "Armor-Piercing Ammunition". Battle armor infantry are very tough, but under that armor is a soldier who can be killed. It seems reasonable that if a battle armor unit is hit by armor-piercing ammunition (in spite of hitting with at least a +2 modifier), that there should be a chance to kill the infantry without destroying all their armor first.
In support of this, TO, p. 108, describes optional rules for penetrating hits against battle armor. Briefly, on any hit vs. battle armor, roll 2d6 instead of 1d6 for location. If you get double-number, that battle armor is destroyed, even if there was more armor left.
At this time, I could not find a rule for this. Thanks for your consideration!
S.gage
