I hope you are happy with those groups cause I sure would be!
I do get a vicarious pleasure watching a reloading expert breathe new life into a ~125 year old rifle.
I got a DR partially as a reloading challenge to regulate non-standard bullets but you have shown me a whole 'nother level. Thanks!

Last question: did you use a filler in that 11mm load?
Modeling your cartridge in QuickLOAD (with a fair helping of salt) shows a peak piezo pressure of
around 10.5 kpsi and a fill ratio of 45% (using H4198).
H4198/AR2207 happens to be the most versatile powder for loading the 444 which is my narrow minded focus.