I have had very good results with a wide range of bullet weights with IMR-3031 I have made some as light as 39 grs that shot about 2' groups at 100 yards when loaded at minimum (3200fps) at near max about 3600 they patterned on the paper instead of grouping. If I were in your place, I would also go for the highest power optics that I could afford with a minimum of 24 power and preferrably 36 or 45. My thought would be when you get this Savage 223, do some testing with copper jacketed stuff and prove the capabilities before moving onto RF jackets. In terms of primer selection, I would say to stay with Federal 205M's or CCI BR4's Match Grade Primers for stick powder and magnum primers for ball powders but some may disagree on the magnum primers. It is also my opinion that there are a lot of different variables in the works here and you won't know what is best until you do some testing.
I have 23 different powders in my powder cabinet :) My opinion is that if you ask 10 different people you will get 9 different answers as loading is a personal thing and there are so many choices available. I also tried some reduced loads with Blue Dot based on a couple of articles and could not get blue dot to shoot for beans. When I was testing RF jacketed swaged bullets, I had some acceptable results from H4198 through my bench guns.
