I am not a hog hunter, but from what I've read, all three will work nicely for you. If I were 15, and buying a rifle for the first time, I'd opt for the 303British in a #4 SMLE (Short, Magazine, Lee Enfield). They are not expensive, they hold ten rounds of amo, reasonably accurate, and, they will likely shoot right through a pig with little difficulty, and they are about as reliable as you are likely to find.