If it has to be a pistol, I'd opt for a .40 or .45.
10mm is good, but it's not something you're likely to shoot very often. Ammo is hard to come by unless you buy it online, which right now is running low on stock. Locally you're going to pay out the rear for it if you can even find it. It's just not a popular cartridge.
The .45 ACP itself would work just fine, and if there's any doubt, bring out the .45 Super. Same dimensions as the .45 ACP, just thicker brass loaded to higher pressures for more power. I load for it and shoot it out of my Gen4 Glock 21. 255gr hardcasts at over 1150 fps. Buffalo Bore and a few others load for it, and it's powerful. Plus you have a weapon that you're likely to shoot more often as .45 is popular. It would work in the 1911 with a tougher spring.
Same deal with the .40, it's popular and if you want warmer loads, you can get warmer .40 loads that will deal with anything (read: within reason) that will be shot with a semi-auto pistol. With a 6" G24 barrel and handloads it's easy to get 200gr hardcast or JHP at over 1200 fps and 180gr hardcast or JHP at 1350+.
Glocks and Single Actions
Last edited by Ruger45LC; February 5, 2013 at 08:41 PM.