I like Winchester Supreme Turkey #6 copper plated lead for 2 3/4 & 3" loads. They are excellent ammo for the money IMHO. As other posters have pointed out, you will have to try several types of ammo to see what patterns best in your gun. I use a Carlson XXFull ported turkey choke in my shotgun. If you decide to use the Federal ammo that uses the flitecontrol wad, you want to make sure you use a non-ported choke. The wad is designed to stay with the shot column, & the ported choke slows down the wad prematurely. Good luck with your turkey hunt!
George