A client of mine took a .45 auto in the arm right above the elbow. It ran up his arm and came out his back. It was a grievous wound, messed his arm up good, and made a big hole coming out, but he still had plenty of fight left in him.
A murder trial going on today involves a woman shot in the breast with a .357 JHP. The bullet (according to the paper) entered her breast, went through the soft tissue to her liver, penetrated her liver, and came to rest in four pieces near her spine. It took her a couple of hours to succumb to this shot. She lost a liter of blood internally.
A case that will soon wind its way through our system involves an ex wife who (allegedly) took a borrowed .380 auto to a home where her ex husband was sleeping, and shot him through a closed glass window into his neck. He apparently did not even wake up, but a week or so later was having pain in his neck and shoulder and a hospital determined he had been shot. The bullet was later found in an interior wall of the home after it penetrated a few other walls.
Bigger is probably better, but a lot of luck (good and bad) is clearly involved.
I don't carry often, but when I do it ranges from .22LR to .38 +P in an LCR. I'm a professional person, so if I can't carry it comfortably in my pants pocket, it just does not get carried.
I wouldn't want to get shot with anything.
edit: I forgot about another one that will go to trial in a month or so. Victim's buddy empties some kind of a Browning .22LR into victims chest. Shooter is in front seat, victim in back. Victims appears to be dead, but when car stops at light, he gets out of car, runs away, and dies on side of road, iirc.
Been a lot of shootings lately, including a home invasion that did result in a DRT for the invader. Don't know what caliber was involved in that, but it was a handgun.