As always there are so manyvariables. The patterning board is the one who can answer that question the best.
What size of shot are you using?
Decoyed birds or pass shooting?
What brand of shotgun? With changeable chokes?
What brand of ammo, and at what speed?
Typically Improved Cylinder is a good start for steel shot. But it is always best to pattern a shotgun before taking it in the field. Not all shotties(chokes) throw shot out the same way.
Set up a piece of paper with a 30" circle drawn on it at 40 yards. Shoot at the center of the circle. Try this for all of your shot & choke combinations and find which gives you the best coverage without going to too small of shot size. Late season ducks and commercial ammo, you should start with #2's and go up. Geese, BB and up.
SS