I've never loaded shells for waterfowl so I assumed bismuth could be detrimental for steel barrels. I have a friend who like a lot of us are always trying something different with the reloads. He was using some foreign straight walled hull and Claybuster Win/Rem wads, the 1118-12ga. I told him he could do it, but would loose a little pressure and velocity. I gave him a handful of wads meant for a straight wall hull to try. That was it, for some reason he switched immediately. If I remember, he said he cut one open with the wrong wad and found powder leaking by the wad. If powder can leak by, how much pressure will leak by ? Yes they can be used, but why do it if you can just as easily use the correct wad ? A 3118 or 2118 work in Fed style shells. Go here to check em out
http://www.claybusterwads.com/index.php/federal-style
If you want stack height higher go to a wad that holds less shot. The shot cup isn't changed much, but the cushion height is.