That last set of targets is interesting. If I'm interpreting them correctly the rifle shoots better the more you shoot, with that particular load. Your L1 and R1 shots are spaced further apart, on both targets. Then, as you shoot more through the barrels the L and R shots converge. It appears to either be a result of the barrels warming, or fouling. When you get to the second and third shots the L and R barrels are printing much closer together.
I would think this is the opposite of what one would desire. Although not all rifles do it, what is most desirable for me is for the first shots out of a cold, clean barrel to print where the sights are. I hope more load testing proves that not to be the case, and makes the group sizes more consistent, and smaller.
Were the bores lapped?
