litterally any of those will kill a pig no problem, with the right ammo
What kind of hunting will you be doing?
Tree stand or blind? = .308 with Remington Core lokts or similar...high dollar ammo is a waste on a hog you should be shooting in the head anyway
Stalking? = .30-30, again with corelokts or similar
truck or buggy hunting, 12 ga is probably perfect if stoked with 00 buck and maybe some slugs in reserve
save the .357 for back up or finishing, unless you are supremely confient in your handgun abilities....hogs arent paper targets and good shot placement is important for solid kills...tracking hogs sucks
popped this guy at 250yds with a 110gr .270 Win
got this one with a 10/22
buddy killed this one with a .257 Wtby, overkill imo
buddy killed this one with a .243
if it launches bullets, chances are its killed hogs, so use what you got, take good clean shots, and remember, hogs aint T Rex so you dont need a howitzer to kill em.