I believe the original 'study' claimed that ducks in the wild were ingesting lead shot and dying. I think that the study was subsequently discredited. I always figured the raptors would be the real victims. I know that I was getting an unacceptable number of wounded birds so I went looking for something better. For me shell costs are irrelevant as the ducks have disappeared from this area (S.E. Colo.) over the last 10 or so years. I have been checked a few times but have not been asked to show my ammo.
C.G.B.

My understanding is that the study was based on overutilized areas like state game areas, where there was a lot of shooting. Can't imagine it would ever be an issue on a lightly shot area

BPI reloading manual for steel is a excellent resource and they recommend using a mylar sleeve in the shotcup for extra barrel protection