209:
Yes, data is out there if you scratch around for it. There are a number of loads, including practice loads, in Graeme Wright's "Shooting the English Double Rifle."
Another shooter posted XMP 5744 loads from the ballistician at Western Powder on AR, and I have loaded some mid-range stuff using the Hornady 300 in anticipation of my rifle's arrival this afternoon.
I love your rating of the G1S stock! Ain't it often the truth. I have my fingers crossed for some figure in mine.

Port: Any chance of seeing a video of you shooting your No. 1 at speed? You must have very nice technique, and a reworked safety eh?