So I'm wanting to pull out the 1st shotgun I got and use it waterfowling. It's a 46 y.o. Ithaca Featherlight 20 ga. 2¾" pump.
My understanding is that bismuth is ok to use. What are ya'll thoughts and suggestions. Thanks

bismuth is good to go, has breathed life back into lots of old waterfowl guns

The featherlight has an aluminum receiver rather than steel, so I would stay away from any hotter than normal loads or it could end up having some headspace or other problems. And your barrel is not going to be rated for steel shot or tungsten. Bet it's a full choke too. Your pretty much limited to stuff like custom reloads or Classic Doubles and Rio Bismuth loads. Hunting with that shotgun using safe non tox will cost you about $2-$4 a shot using commercial ammo. If it were mine, I might take it out a couple times for nostalgia reasons, but I would not want to use it all season.

check out RST shells in Pennsylvania. They load a variety of shells. Older vintage o/us and side by sides is what they load for pretty much. Keeping everything relatively light and non toxic shot that is safe in those older barrels. And they will also load up a complete custom load as long as you order 10 cases. Paper hulls are also an option. As well as 2" and 2-1/2" shells. I have shot many different loads, and most of their shells will absolutely "splatter" on a pattern board, in most of my guns anyway. They are also priced cheap for what they are.

Thanks Guys, I've learned more about that shotgun in an hour than I knew after 46 years! It's a mod. choke and being an older man I tend to work my dog and let others shoot, so I think the Rio Bismuth will be fine. Thanks again.

My featherlight, 1952 vintage, has a steel receiver.

Kent Tungsten Matrix may work too.

Yea your right. It was the ultralight that had the aluminum. I was going by memory. That shotgun was made for so many years spanning at least 25 versions, so with M37s having different names like featherlight, featherweight, ultralight, ultra-light.... it is easy to mix them up without pulling out a book. There was even a waterfowl version. I still would not want to risk shooting any hotter than normal loads in it.

Speaking of Tungsten Matrix, I shot some heavy 12 and 20 GA Tungsten Matrix last year on Mountain Sharptail and Sage Grouse. They had some kick to them too. Ammo cost was not a big deal for that hunt considering I was hunting a bird with a possession limit of 2 that I may never be able to hunt again because it is about to go on the threatened or endangered list. But If I were a rich man and money was no object, that Kent Tungsten Matrix is all I would hunt with.