I am not a dedicated waterfowl guy so my experience is rather limited. But when I drag out my old vintage French guild gun for waterfowl I use Bismuth. I tried the Kent shells but they recoiled too much out of my little game gun. Last year when in Alaska I fold a nice Canadian goose with a 2-3/4 BB Bismuth load out of my SxS while pass/jump shooting. I've used #4 on ducks too with good results.