I have 3 20ga that I use to hunt geese, ducks, doves and now I am planning on using it too hunt turkeys. I have had my wifes 11-87 Premier set up and she took a tom 5 yrs ago with it.
I bought a Stewart Wrights "The Swarm" choke tube and Hevi-13 shot in 6's and a scope. I also used a Primos Jelly Head with same shell. I went with the Hevi-13 due to its increased pellet energy to compensate for the lack of a large shot charge.
Stewart Wright choke tubes set the World Turkey shoot standards and have won more championships and World Shoots than any other tube available.
I am going to use my new Baikal 20ga Sporting Clays O/U with TruLock chokes, Hevi-13 in 6's and a handload 3" of ITX shot in 4's as back up. Both with TruLocks Turkey .565 tubes. Devastating out to 40yds!!!