Recently, I've been burning up partial boxes of left over bullets in 2 different 223's using IMR 4064. I'm getting sub 1 inch groups with many loads, although I have no idea of what the velocity is. I'm doing a quick load work up with each bullet to find a usable load for the 40 -50 bullets of a given style and then burning the rest practicing my field positions. 25.0 seems to be the sweet spot with numerous bullets.
I'd guess that you'll get satisfactory accuracy but lower than ideal velocities with the 55 and lighter pills. I'd like to hear how you make out regardless.
