I have been doing reading here that harder BH will normally shoot more accurate at higher rifle velocities. I shot a 1.250" group at a 100 yards with a WQ boolit BH of 15. I tried the same load with an AC boolit with a BH of 13.4 and shot a 1.190" group. So my softer boolit was more consistent.
The load was a 35.5g load of H110 out of my Ruger American 450 bushmaster using a Lee 310 with a GC.
i would assume the softer boolit expanded better to grab more grooves of the rifling to make it more consistent?
Well, my AC boolit has hardened to 14.3 BH so we will see if groups open or stay the same.