Those are interesting results. Actually not all that bad of shooting. If you considered that center dot the point of aim on a deer, you would still be eating venison if you aimed middle shoulder.

I think you simply discovered that the rifle likes Pyrodex over Triple Se7en. Perhaps the FFFg threw the rifle into fits. Shooting sabots, my rifles like the FFg over the FFFg. Shooting conicals on the other hand, the fast burning powder I think gets them moving faster and gives me better accuracy.

Nice testing there...