fixin to send a model 12 16 to sumtoy to play with.
Any suggestions as to what factory shells to send along with the gun?
While expensive, you might contact Nitro Ammo Co. They made up some 16 gauge shells for a man in a thread below. They will be Hevi-13 HTL shot. I believe he bought #7. See "Next Slam--16 gauge"
PM him and see what he steers you to.
I used Nitro Hevi Shot #7s this year with great success. William at Sumtoy built me a choke and the gun was a pleasure to shoot! I took birds in FL, SC, OH and WY this year with the set up.
William took great care of me and I am going to have him build many chokes for other projects in the future.