We have a similat situation in AL. On public lands, only the firearm legal for the specific season at hand is legal for hogs. Thus, in small game season, only a shotgun w/ bird shot ( the reg gives a specific size) or a rimfire rifle is legal a lot of the times, .......or bows.......or muzzle loaders UNDER .40 cal.
Guys who want to hunt hogs on the WMA's during small game seasons are for the most part using scoped .22 mags w/ heavy bullets, some even FMJ, and aiming for the neck skull junction/base of ear.
I would not intentially brace a hog at any range w/ fine shot from a shot gun, would not really trust buck past 25-30 yds from a tight choked gun, and would prefer a slug or real rifle.