Might have resolved it…
Have the same gun. Shot three 3 1/2" shells out of it when I first got it. And said nope not today Satan. Went to the 3" Longbeard #5 with an Indian Creek .660 choke and it was lights out. Now I shoot 2 3/4" #9 TSS with the same choke and it puts up amazing numbers at 40 yards. Definitely a killer but those 3 1/2" shells rattle the old sphincter.