IMO, the single shot and bolt action pistols chambered in rifle cartridges kinda defeat the purpose of handgun hunting, as they are essentially stockless rifles with slightly bobbed barrels. But to each his own. For me, the sport is in using a conventional handgun in a handgun chambering, albeit a potent one. Here in CO,
very heavy 10mm or .357 Mag is minimum by law (550 ft/lbs @ 50 yards). But the larger .41 and .44 mag easily meet the criteria, and will cleanly take a deer with good shot placement at responsible ranges.
Then, of course, there are the powerhouse .454 Casull, .50 AE, .460 S&W, .500 S&W and a number of proprietary cartridges in the 1,500+ ft/lb range. These are all more than enough for deer, and suitable for elk to 100 yards or more.
An Encore is about your only choice unless you use an X frame Smith
For what? Grizzlies? Heavy .357 and 10mm are plenty for medium game at reasonable ranges. The venerable .44 mag has been dirt napping Bambi and bigger critters for a long time, with less than half the energy of the .460 or .500 S&W.
I have a Kel-Tec PLR in .223 delivers the slugs at 2900 fps.
Not with 55 gr. ball, it doesn't. A shade over 2,600 is average. That is both advertised velocity and real world chronograph results. I've checked. 40 gr. handloads managed a little over 3,000 though.
http://kel-tec-cnc.com/plr16.htm
But .223 isn't legal for big game in many states anyway, nor are the 10 round mags the PLR comes with.