I shoot the Super Max choke in my 870 with 3 1/2" Rem Hevi-shot 6's. It throws patterns like a rifle. I would try the Super Max that you have first. It's constriction and design is made to handle shot sizes 2 through 7 1/2 Hevi-shot. I would personally like to know how it patterns the Nitro Ammo myself. Let us know.