ar-15.com has something called the ammo oracle. There was far too much info for me to remember there. I highly suggest you read the essays there.

I've known several men who killed other men with M-16s. The two who talked to me about the wounds M193 made were impressed. The one who shot people with M855 wasn't impressed at all.

I fired a three round group with my M-16A1 clone at fifty yds. that could be entirely covered with a dime. The ammo was Malaysian M193 and i was using iron sights.