I noticed that the local SW has 410 bismuth #4's in stock. A friend of mine is a member of a duck club and a member there regularly uses a 28GA for ducks. He is thinking about using a 410 and the members are not very happy with this. Their concern is that he will be crippling too many birds. While I am tempted to buy a couple of boxes of 410 bismuth just to try it I will refrain from doing so and stick to my 20 GA duck gun. If I wing a clay target it does not fly away and suffer.