also had a LOT of duct tape and paper plates.....
Were you just shooting at paper plates? I would recommend shooting at whole sheets of poster paper. Results can be deceiving if you shoot at too small a target. Sometimes the center of the pattern may miss it entirely.
2. There are some differences between loads - - but a LOT less than the ammo manufacturers would suggest.
Hmmm, if you didn't see much difference between lead number 4's and Hevi-13 number 6's then all I can say is your results are non-typical. Not disputing them. Just saying they are unusual. Usually lead 6's will pattern much better than lead 4's and denser than lead 6's way, way, better than lead 4's.
6. As homage to "Box O' Truth": it's fun to shoot stuff.
Total agreement here. A day without gunfire is like a day without sunshine. LOL!