.450 Bushie, .458 SoCom. East of the Mississippi, any AR10 in .308 or see if Wyndham will fix you up with a .358 Win. (uh, hel-looo ..)
Not likely or not easy? .22WMR AR - Google Search
Savage A22 Semi Auto Rifle .22 WMR 21" Barrel 1 Rounds Synthetic Stock Blued 474 | Cheaper Than Dirt
Rossi RB22M Bolt Action Rimfire Rifle .22 WMR 21" Barrel 5 Rounds Weaver Scope Mount Synthetic Stock Matte Black Finish | Cheaper Than Dirt
If AR is about 'round count', no caliber is cheap to shoot. (please don't suggest .. even mention S&W's plastic .22 LR AR) If it's about picking a hair and hunting with a 4-5 rd mag in a caliber other than 5.56/.223. 7.62 x 39, or .300, well there are the superb 6.5 Grendel and .300 Ham'r. That said:
I have .22 Mag Heritage revo, Rem 597 semi-auto rifle, and CZ 452 LUX. When you see how nicely centered it's ballistics and cost are between .22 LR and .22 Hornet, you'll find a lot to like about whatever you shoot your ammo through. Some calibers are just too much fun.
btw, I've shot more 'coons, coyotes, red & gray fox, and feral cats with .22 Mag than with .22 H, .22 LR, and .17 HMR combined. No lost game (vs .22 LR & Hum'r) & all one-shot kills. "Some calibers are just too much fun."![]()
Years ago I bought a 17, I wasn't happy with the results shootings critters, I went 22 mag and haven't looked back, very underrated round..