The tax stamp could easily be restricted to be spent in waterfowl enhancement only. BATF already is use to special taxes like for full auto guns and that goes back to 1934 as I recall. Do we just amend it so lead shot on waterfowl sing black powder if needed. Just get your foot in the door. RST could make a run of black powder ammo for the first year. Start small, be honest about it....
This is what I was thinking Jon. I think the dems could easily be on board for this. Have the folks not only agree to backdoor registration, but pay for it. It could also be a path to go completely notox, because it's the same old, if you like your lead, you can keep your lead, if you can afford to jump through hoops.
Just speculating out loud. Besides, haven't you heard, just run some #7 steel through the old gun and all will be just fine, in someone else's world.