From what I have read on the 300 WM and my experience, the 300 WM shoots best with max or close to max loads. But all rifles are different so you have to work up to max. I loaded my Ruger with 72 gr of IMR4350 and 180 gr bullets forever but have been experimenting now with IMR4064. Accuracy and velocity are very similar, but recoil with the 4064 is noticably less.