Just with my limited knowledge of hogs, I'd say you'd just make them mad with bear mace and you might get et. If you're that close to a hog, you're already in trouble.
I checked the SC DNR site:
Legal weapons - shotguns, muzzleloading shotguns, bows and crossbows. All other weapons or methods are prohibited including rifles, pistols, buckshot (50-11-500, Reg. 123-51).
I see buckshot as a prohibited method.
What I didn't see was what shot sized are legal for turkey. In KY, you have to be careful-- #4 is legal. #2 is not. In Ohio, #2 is legal, but nothing under #6 is. SC might have that sort of restriction; I don't know . I'd dig into what is said in 50-11-500, Reg. 123-51 and also read a few pages to either side.
You could make the case in KY and Ohio that some of the Nitro loads are not legal-- in some, there is up to size #2 shot and down to size #9 . I haven't heard that the state is going to get on you for Nitro loads, but then it took a couple of years for KY to state openly that they would prosecute guys for bringing remote-control decoys into the field. One thing I know they don't like in KY are the Remington Duplex 2X6 loads.
If there is a state-specific hunting forum in South Carolina, you might want to find it and check in with them. I hunt mostly Kentucky, and KYHunting.net, sponsored by WingSupply.com, is an invaluable resource. There are enough CO's on the site that you can usually get a bonefied answer to just about anything from the guy that would be writing your up, or at least his buddy. What I like is the ability to discuss not only what is and isn't legal, but also what "best practice" is-- such as how to avoid the gray areas that might get you written up, even though you could probably beat it in court.
For instance: I had a question about my son's youth license. He turned 16 this year just after Turkey Season ended. Did he need to buy a youth license, a youth turkey tag and an adult turkey tag for fall hunting. The law was vague. The answer was no: the youth tag was good until it expired. However, he had to buy an adult deer tag. It was also explained that when my youngest turns 16 in a few Aprils from now, it's okay to buy him youth licences and tags even though he turns 16 during the season.