I will also give a plug for Bismuth shot. I have been using it since it hit the market in late 80s or early 90s. They went out of business for a while but another company bought the rights to the name and formula and it is now back on the market and Cabelas is handling it among others. You can use any choke you can shoot lead through with it. It flat kills ducks and geese, it will kill turkeys. Link below for Bismuth shot at Cabelas. Not cheap but neither is heavy shot.

http://www.cabelas.com/catalog/searc...h-All+Products