Big Tom...here is what CAN happen when a .380 hollow point hits bone. This was only TWO INCHES penetration.
http://www.youtube.com/watch?v=AD4Z5hKg8zs
After having inmates as patients, I've decided I want a round that can hit vital organs, even if I have to shoot the bad guy through the arse to get the bullet there. My normal ccw carry is .357 158 grain SJHP that I have chronographed at roughly 1300fps out of my full size revolver. Out of my 38 snub it's buffalo bore 158 grain lhp that gets an honest 1000fps.
I carry the .380 only as a backup or when (as is the case right now) my main weapon is out of commission (presently at the gunsmith fixing a sight broken while I was hunting...and for a 30k round tune up)
Since more than half of the rounds fired in self defense are MISSED SHOTS (ie all of the kinetic energy is available to injure an innocent bystander) I'm more concerned with working on my aim, point shooting, shooting from retention...ect than I am about the remote, but very real, possibility of injuring an innocent via over-penetration.
If, God forbid, I have to shoot, it's because I have no other alternative and my things have digressed to the gravest of extreme circumstances. If I'm stuck with my .380 (which is what my two daughters are presently learning pistol shooting with) as a S.D. gun, I need to place the shots well, and I want penetration that is not encumbered by expansion.....this is a VERY under powered round that cannot simultaneously give BOTH reliable expansion and penetration....ever. I choose penetration. If you choose expansion, I will never throw stones...it's your rear end n the line.