I'm not giving up yet!!! However, I think it's a long shot that this gun will shoot 1.5" groups consistantly. I have never seen a gun go from shooting 5" to 7" groups down to 1".
Usually with my Knights I would get 1.75" to 2" groups and then I would tweek it down to a 1" MOA, by changing up primers, sabots, and powder charges.
BP: The 78 grain weighed is the same as 110 volume measured. This 78 grain load is sort of the bread and butter load for five of my ML's. So I thought it was a good starting point. Your point is well taken though.
I may try some Triple 7 powder and see how this shoots.