The down side to using smaller calibers is, if you do screw up the shot, Hogs often tend to stop bleeding quickly (the wound can pucker shut fast). You may never find that Hog. If they make it very far they are likely to head for brush so thick you can't walk through it. Bring a machete.

Plan for the worst and hope for the best. Stalking, you often have a snap shot, wounds are a high probability. You seeing them before they hear or smell you is unlikely, both of you discovering the other at about the same time is more likely. A quick follow up shot is a plus, as is using a bullet big enough to open up a wound big enough to bleed (and follow).

Hydrostatic shock doesn't mean as much for a Hog as it does a deer. So high velocities are less useful, bigger diameter bullets are the preference.

A survey I read rated Hogs as about the same as Elk, as to how much rifle it takes to reliably bring one down cleanly. Elk are about two or three times the size as your average Hog.

Big moderate velocity bullets are preferred for Hogs around here. 7 mm being on the low end, all the way up to 11.4 mm (45-70), 8X57 or 8X64 mm being the most used.

I use a 35 Remington (9 mm) 200 gr Silver tips (from my stash, they have discontinued this bullet) or soft point core lokt. for stalking. Sometimes I use my slug gun.

Practically and ethically, IMO use enough gun.