I use a Mossberg 500 and use their factory choke its an xxful turkey choke. It will knock a bird down at 50 yards for sure. I would trust it out a little farther. But for me the closer the better. I havent taken a shot over 50 yards yet, but I know it kills at 50. I make sure I pattern it and have found that Federal 3" Magnums 2 oz 5 shot shoot best from my gun...