Neat looking gun.
There is one thing you can be looking at and that is the shot counts in the 11"or even 12" circle.
Your inconsistency could be just just right there . Also check a 11" square for pellet count on target to target.
Now the big differences down to 100 from 150? Have never seen it except when someone gets the shells mixed up. Not speaking from experience of course. HW 6's to hw7.
Cleaning is a big thing with some loads . A good clean can bring new life to a gun,load and choke combo.
Any cleaning solvent or oil in the barrel is a good way to get pattern to jump around.
Deep clean all you want, polish all you want.But get that stuff out of the barrel when you finish. Denatured alcohol works great, learned that on here. Some thing that evaporates and leaves the metal squeaking clean.
I would hate to think of the loads we shot and said no to that would have been much better if we had always done it
before.lol Had even sold a gun to a friend that cleaned the heck out of it and all he had to get the oil and gunk out of the barrel was breakclean or carb cleaners. He went and shot the gun with Magblends 3"shells at 40 yards and got in the 200 in the 10". I said no way and went up to check it out myself as the gun had not come close to that before. Sure enough it did and got the Federal hw7 at 180-190 too. Good luck.
