Talk:Heavy Cannon vs Auto Cannon

Jasonred: During the early part of the game, the most common enemies (the only enemies?) are Sectoids. Since a sectoid is so very delicate, even a near miss from a AC-HE round can kill it, thus changing the kill probabilities a bit. The HC has higher firepower per shot, but a great deal is "overkill" in this case.

I don't think the above is true so I've moved it here for discussion.

For direct fire / direct hits, there is no overkill. Because direct fire damage is 0-200%, for unarmoured targets the kill probability is linearly proportional to base damage (where Health < 2*Dmg). For armoured targets, kill probability rises better than linearly with base damage. So there is no overkill.

But you are talking about HE area damage (near misses). I actually did not model near miss effects in my firepower calculations. In theory there is an overkill factor in area damage, whenever 0.5 * Base Damage is > (Armour + Health). But in practice, even weedy Sectoids are not this weak. Keep in mind a near miss is 10 or 20 base damage less than a direct hit. So in practice, area HE kill probability for these weapons has no overkill and is better than linear with base damage.

If we compare AC and HC as HE area weapons, the HC has a greater lethality over a greater area with a greater accuracy. I have not done the sums but my gut feel is that it will outweigh the better fire rate of AC auto.

By the way, the firepower advantage I'm quoting is not per-shot but per unit of time or per TU. Also, Floaters are quite common in the early game, and the terror units associated with both Floaters and Sectoids will be encountered toward the end of the first month, when AC and HC are still state-of-the-art weapons.

Spike 06:13, 27 February 2009 (CST)