I've been working up loads for the 300 wsm.
With the 150's I've been getting the best results with H4350
With the 165's. IMR 4831 has been giving the best results.
With the 180's and 200's. Reloader 19 is working the best.
I'm getting the best accuracy at or just short of maximum for my rifle.
The denser the load, the better the bullet flies.
It doesn't seem to matter whether I use CCI 250 primers or WLRM primers.
Of the bullets I've tried so far, the Hornady Interbonds, Nosler Accubonds and Partitions fly the best. I was going to try the Failsafes but, I chose not to shoot moly coated through the barrel.