Don't gun hunt turkeys much anymore, but when I did I used 3.5 inch shells. They patterend great, but I did a lot of research and range time. Now that I'm older, I would probably use the 3 inch due to the damn recoil. Them sumbitches kick like a mule. Getting too old for that. Still use 3.5 inch on geese though. Nice to have the extra insurance.