[thatguy96]

Look, this has been done before, and people simply changed the weapons to account for it. If you want both HE and AP, then create two seperate versions of the gun to show this difference, equip the artillery units with both (splitting the ammo values accurately), and then rescale the points to where you think its reasonable (the cost calculator's result would have to be modified because technically its not two guns). Then, in your scenario, you specify that one or the other "gun" should be disabled when firing by the player.

I also don't think that AP artillery ammo would create the holes you're imagining. Unless this is a combination round, with a large explosive core in addition to its AP capability, it should do most of its damage through kinetic energy (thus good for taking down fortifications and other large static objects), not through chemical energy (not good for engaging moving or scattered targets). I might be wrong, but this is generally the trade off in effects.