I've only experimented with the Prvi Partizan 174 gr bullet and found that 42 grains of AA2520 powder gives the best accuracy in both my P14 and No4. I haven't tried it yet in my Lee Metford Cavalry Carbine and my Long Lee.
(I was looking through an old notebook last week and found that I'd jotted down this very combination five years ago on a mate's recommendation and had then completely forgotten about it.)
