RE: 16 Guage
It'll work fine. I used my dad's old Browning A-5 16 guage (still my favorite shotgun of all time) for my first duck gun. If you're wanting a lighter shotgun you may consider a 20 guage because a 16 carries like a 12,but doesn'thave the same knockdown. Also, 16 guage shells are becoming harder to find due to the popularity of the 20 and 12 guages. Rick Dunn from Echo Calls uses a 20 guage in some of his videos and kills ducks fine with it. Good luck.