is your 74R a single or double? If it's a double, I'd load up whatever regulated best with it.What I forgot to mention I have a 9,3 x 62 and using the above 285/6 Oryx/A-Frames.
I also have a 74R and did not want to duplicate the 62mm load. Was thinking of a 250gr, but most my hunting is at short range. 50-150m. The reason for the Q about the 320gr