I always use nylon or leather shooting rest bags. A nice front bag with a v notch type rear one that I squeeze win my non firing hand to raise or lower my elevation. Its what I use to accuratly group and zero my rifles at 100 yards. I also use ballistic tables so I know where the round will hit at different ranges. Some people use something that locks the rifle in to eliminate human error for zeroing and grouping. Im happy with the bags. I can only shoot 100 yards at my range so I don't really need a precision front rest.