I have done a number of guns this way including one home made barrel. What you need to use depends on why you are doing it and what you hope to accomplish. To polish a bore I use jewlers rouge and PRB ,I simply put a light coat of jewlers rouge on the outside of the patch. If you have burrs or rough spots you might want to use valve grinding compound or JB bore paste. If you would give us more info we might be able to help more. One of the important things to remember is not to go over board, when you grind or polish a barrel it takes shots off the life of the barrel. Lee