I guide hog hunts in North Tex, A lot of my hunters come in with 22-250 and .223's, these are experienced shooters and do well with these calibers. It is shot placement...
I myself use a T/C Encore, 22-250 for small stuff and .300 Win. Mag. for the larger. Otherwise the 7mm.08 is a good all around caliber, it will put a smaller hog down in vitals, neck or head shot, but a larger boar would be doubtful unless you can hit 'em in the boilermaker every time.