45 ACP FMJ will shoot through two full-size gelatin blocks back-to-back and keep going.
45 ACP with expando bullets penetrates to the same depth as all other major calibers shooting expando bullets.
So what's the issue?
Remember too, there's 45 Super. Works on most 45 ACP guns without any modification. Except you might want to see how it functions with heavier recoil spring to minimize beating the gun up. 45 Super uses a case that is thicker in the web, because the first limiting factor on "hot-rodding" 45 ACP is the brass cartridge-case, and not the guns that shoot it.
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Only issue I see is 45 ACP guns tend to be the heaviest, and carry a few less rounds. Maybe somebody will bring up 10mm and "bears" or some such. OK, bears then. If you're gonna shoot a bear with a handgun, be sure to shoot a bullet that doesn't have a real conical-shaped nose. Because any bullet at handgun speed does risk bouncing off bone on its way to wherever bullets that bounce off bone go. Remember, you are 99.9% more likely to be attacked by a crack-head in a wife-beater than a bear. Probably even in Alaska. So there's that.
You shouldn't have to spend a fortune on 45 Super ammo, because how many bears will you really have to shoot?
Now, if you want a lightweight, high(ish) capacity carry piece, get you one of the plastic-fantastic guns that are popular these days. Then and head on out to the 7-11 for a corn dog and some smokes. Aint gotta dress up like John Wayne to go everywhere. Not that I would hold it against you if you did.