I have a 21" 11-87. It began life that way though. I've had pretty good success with a Briley Hevi-Shot Turkey choke as well as a Rhino. I haven't worked with it as much as my Vincis. However, I routinely get low 200s in the 10" for 3", 2oz Hevi-13 #7s and my #6 "Old Whites will yield about 120-ish at 40yd. That's not sterling performance, but it's quite functional.
What exactly has he tried so far and what kind of numbers is he getting at 40yd? Is he running lead or HTL loads?