I have hunted ducks and geese for several years with a variety of guns and have never used a full choke with steel. I've found you never need to go more than modified to get a really tight pattern. Most of my hunting is done with Improved cylinder and I don't go to modified till late in the season and sometimes I just staywith I.C. especially with high velocity steel (2,bb,bbb) I would think that if you did find a full choke for steel (most chokes list modified (lead)=full (steel)) it would just blow your pattern.