RE: 12 gauge 3" shotgun for ducks?
I had good luck with 2 3/4 and 3" federal speed shok in #3's for ducks last year, you can kill anything with a 3" shell. For geese i prefer 3 1/2" but i have killed lots with 3" shells using BB shot, 3" hevi-shot is really good for geese in #2's, have funa and good luck with your shotgun.