If you use buck shot stay with the 00 or 000 buck. I shot my 10 pointer with 3" magnumfederal premium 000. But like I said in my earlier post I wont use it anymore due to the lack of blood there was even with the bigger buckshot. When I skinned him there was a whole load of #1 in him that had healed over from a previous season. It didnt penetrate for crap. He survived fortunately but thats not the point. Spend the money get a rifled slug barrel and shoot the premium slugs. You wont regret it at all.