Reloaded shotgun shells with non-lead alloys

Hello, I reload my own shotgun shells. Can I cast non-lead alloys, say bismuth-tin, and load them to hunt ducks? What proof shall I carry with me to prove this? Is it legal to reload shells that previously held lead shot with non-lead shot to hunt ducks?
Answer: 
As long as you reload your shotshells with a USFWS approved shot, you may shoot waterfowl with reloaded ammunition.
Answered on: 
Monday, May 4, 2015 - 4:12 PM MDT