When I was shopping for a pistol to carry while hog hunting, I tried my Brother-in-Law's .44 magnum. Lots of recoil, and LOTS of noise. My 9mm is definitely too wimpy to use for hunting, but for a finishing shot on a wounded animal it's fine. Even an angry hog is going to think twice about continuing straight at someone shooting at them, regardless of the caliber. Besides, there's no way I would be quick enough to switch from my rifle to a pistol in time to react to a charging hog.
Having said that, I've never had a hog charge at me. Some times they've run in my general direction because I'm between them and the woods they're running for after I shoot, but they weren't specifically after me. I can cycle my bolt action rifle a lot faster than I can draw and aim a pistol.