I mainly shoot gophers and yotes with my AR (.223), .22-250, or .308. I have used every gun in my cabinet including my .50 caliber cap and ball muzzle loader to take down a few whistle pigs.
Really it depends on how long your shots are going to be and whether or not you intend to shoot a lot (cost of ammo and such).
"Worthy is Freedom to only those who are prepared to stand behind their rifles and fight for their rights"
-Robert W. Hambley....A.K.A. Myself-