Lots change for 6ppc. This is some match result from last year and they include rifles/loads.
https://internationalbenchrest.com/a...20Amatrudo.pdf
Myself I use N-133 and 8208 in my 6ppc's that I use varmint shooting. Kind of odd you shooting Brian Rubright and having to ask for load data. I shot Brian 66gr when I was shooting BR and they where sold 500 per box to BR shooters.
Been little data using R-12 with 6ppc
http://stevespages.com/243_6_70.html