A 223Rem with the right bullets will kill near any thing below a certain weight but there are better opinions .
I suspect you are a SA resident & might not have a heap of rifles to choose from but I think you could borrow a larger caliber, as a couple of things Bushpigs are tough, sneaky, desirabe & hard to get a shot at so it is best to put the odds in your favor & I think a 308Win with good 150gr is a nice start (7X57 140gr ?) .
Do you reload & what bullets are available to you if you do, remember the bullet does all the killing ?