I've found 46 grains of IMR 4320 with a Hornady 150 to be superb in a P-14. I back it down a bit for an SMLE action and it is still awesome. If the rifle is up to it, this combination can give solid (and consistent 1 m.o.a. results).
For 174s to 180s, I've found 42 grains of IMR 4320 to be pretty good, but it may be a bit hot for some weaker actions.