H4350 or IMR 4831 should work well for powder. Any primer should work, I would probably go with a CCI 250, F215, or WLRM - it doesnt matter much
If you put a 200 grain Partition or Accubond into the vitals of any animal in North America inside 1/4 mile, the 325 WSM will give pretty good results I'd bet![]()