Before you scrap both Tubes, try shooting different size shots in 3" and 2-3/4-
Try #6's and #4's in both and see how they preform.....If you still dont get the results you are looking for then try another tube.
As for the constriction, I shoot a .660 hevishot tube with hevishot and the results are incredible...
Hevishot, to me is the only way to go.