BSA, what powders have given you best accuracy with the 73? Besides ARcomp that is.
RL15 works great. I understand AR Comp is hard to find. I got lucky and found 10 pounds of it a few months ago. One of my favorite powders. I have used RL15 with the heavier bullets like the 73 ELD match and 69gr SMK. Here is the AR Comp load with a 1 in 9 twist savage:
And then with my Northtech Defense AR15: