10mm Auto. All day, every day.
For the reasons Tamara so eloquently stated.
For the specific carry guns, check my sig.
To add to CB's energy list, in the heavy-weight division, you might check out Texas Ammo's 10mm 200gn loads which use Hornady bullets (your choice: FMJ-FP or JHP/XTP). They exit the muzzle @
1250 fps for 694lbs.
A "heavy & fast" 10mm leaves the .45acp sniveling.
Is the .45acp popular? Sure. Every swinging Jack and their brother has one.
Nothing wrong with the cartridge itself. It's a fine venerable old round, and until I switched to the 10mm I carried a Sig 220.
But for many, the urge to stick with the caliber-herd is simply irresistable, symptomatic of the same instinct that drives lemmings.
This makes it hard to concede the superior aspects of the newer 10mm Auto, the energy figures cited above being but one of it's virtues. Better penetration across a diverse range of shooting scenarios is another. It's all fairly easy to see unless you're stuck permanently in the "ostrich position."
For those wishing to distinguish themselves from the herd, however, the 10mm offers the kind of versatility and energy range few other handgun cartridges today can match. And it does it all from
semi-auto pistols of relatively conventional size (e.g., 1911/Delta Elites, Smiths, Glocks) that are reasonably amenable to concealed carry, unlike, say, the powerful-but-pants-droopin' Desert Eagles, Wildeys or Auto-Mags.
If we're going to talk about
revolvers instead (the original poster's usage context was self-defense/CCW), then you've really changed the caliber-subject altogether. In that case I'd probably be looking toward something like a S&W 657MG in 41 Magnum.