The .380's are still smaller. Those 9mm's make a heck of an IWB gun, but neither pocket carry particularly well.
I don't pocket carry them, but there are a LOT of people on here that do pocket carry the Kahr and the KelTec. When I do carry in the pocket, it is usually a 340PD and loaded with 140gr. Corbon .357's. I hear those work best in that pistol, although they'll beat your hand to a pulp.
I've seen a guy take a .25ACP to the temple, the muzzle was touching his head. The round passed through the optic nerve on one side and exited throught the opposite eye, shattering it. The sinus was liquified, but the bullet skirted the brain, leaving a burn mark on the membrane that surrounds it. They said had the round been much larger, it would have taken off part of the frontal lobe, had it been much larger than that, it would have taken off the front of his head. I stopped the bleeding and got an ambulance there, they said that is why he lived because he almost bled out.
I bring this up because this would be about the most greivous wound you could inflict on someone. Point blank unobstructed shot to the brain through the temple. But it didn't even drop this guy. He buckled for a second, then got back up. If he wasn't blind, he wouldn't have bounced off the walls, but he was up and moving. I had to tackle him to compress the wound.
Now if I'm in a defensive shooting, I want the bigget I can carry. I don't want the guy up running around even if he is bleeding out. Now this experience and reading some stuff written by a guy that works in a morgue led me to believe that even the 9mm isn't sufficient to END a fight NOW. He said most 9mm victims have multiple wounds, .40 and .45 usually have one or two.
So that is why I carry a 10mm, and a .40 when that isn't appropriate; one of those pistols is always on my belt on my pants. I keep a .45 on the nightstand. I save my 9mm and .22 for the range --I don't have anything in between those calibres for handguns. Just .22, 9mm, then the "real" pistols.
My wife, who is recoil shy, carries a G17. I have no doubt that the 9mm will do the job, but I don't have the recoil problem she has so I like the bigger rounds. Still, she isn't a violent person, and I have serious doubts that she could pull a Mozambique drill off if need be. I think a lot of people would hesitate, most armchair commandos dream of the violent encounter, but I bet a lot of people would have problems in a violent scenario.
So if you are in that encounter, you pull a small pistol and hesitate after putting the first round on target, then the guy closes the distance and is vastly superior than you at hand to hand... Now what? Wait for him to bleed out? With the guy I mentioned, that would have taken most of the hour. A shot through the heart would have been faster (good thing he shot himself in the head, huh?) but people have survived awhile with a bullet in the pump. I'd rather my wife carry a lower capacity .45 for just this reason, violence of action, but like the low calibre crowd says, "it is better than nothing".
Then take into consideration penetration. The .380 with ball rounds (which if I had to carry one, that would be the only round I'd consider) is okay, but the 9mm is better. The 10mm can go from shallow to all the way through two people, depending on the load. So in effect, if several 9mm rounds to the chest can fail to stop aggression, the .380 would too, and if a small round to the head can even fail, then why would you carry anything less than sufficient for all encounters? I mean if you could?
I played the which calibre is best game too, and when I landed on 10mm, I fell in love. That round is FUN (I shoot mostly at the range, I don't intend on shooting people, so I try to go for fun factor too... Just being realistic). Also, as a mathematician, I find the numbers for the 10mm to be outstanding compared to other rounds. It truly does lie between the 9mm and .45ACP, but has outlier values that mimic other rounds like .357 and .41mag. Couple this with high capacity mags and a nice rig, and I was set.
I'm never going back. I found my carry pistol, my mind can't be changed. But I thought I'd mention my experience for the fence sitters that are seriously considering the .380 for a primary carry piece. I know they may be easier to hide, but you know what? The right holster and a good belt will hide more than you think.
If you want a good pocket pistol, hey, I guess that is what they do. But just remember that a small pocket pistol is a "better than 'nuthin" option, not the best option. The best option is the biggest thing you can operate and carry that is reliable and easily hidden and put into action. For me, that ended up being the smaller Glocks and the Milt Sparks VMII holsters and a heavy double thick gun belt.