Winchester Supreme XX 3-1 3/4-#6; 3-2-#6, and new Win Longbeard XR in 3-1 3/4-#6. If #5 shot work best for you then try the same shells listed above. Another load is the 3-1 7/8-6 by Winchester that is commonly referred to as the gray box. Shoot at a large sheet of paper when patterning these loads. One or more of these should put you in business. I did not catch the SUPER nova until later so the 3.5" - 2-X or 3.5"-2 1/4-X
if you want the recoil and extra shot.
Another very good shell is the Turkey Thug sold only at Wal-Mart . They are all loaded the same with choice of #4-#6 shot in 3" and 3.5".
Do not use the Federal Flite Control wads in this choke as per Indian Creek disclaimer. It is also good to check on the Win LB loads while you are at it as Sumtoy suggested.