weaverism,
Up front I'll tell you I'm new to LR hunting and that I've never had any experience with the 300 WSM. Be that as it may, I'll share with you what I've learned on this forum.
The 300 WSM is an upcoming favorite for LR shooting here on a variety of game. Most of the experts in here have recommended time and time again the Sierra Match Kings, Hornady A-MAX and Cauterucio bullets - all of which are "intedended for target shooting only". However, the arguments for shooting these types of bullets have convinced me to go with them. I'll tell you, like they told me, that the single most important thing in LR shooting is practice. Good optics, accurate rangefinders, drop charts, etc. all are required but practice is mandatory. Most of the guys here shoot several hundred or even thousands of rounds in preparation for hunting. So before going the length of setting everthing up for LR shooting in the way of equipment, make sure you have a good range to practice on.
I myself got myself a new LR whitetail rig for shooting the 0-700 distances. It is a Rem 700 Sendero in 7 RUM topped with a Sightron 6-24 X scope with mil-dot reticle. I am still waiting on my Hornady A-MAX 162 grain bullets to arrive so I can't tell you how it performs.
Remember, whatever bullet you go with, use it within its design range. Match bullets will work at LR. Hunting bullets may not work at 600+yards as they are intended for impacting at closer ranges and at higher velocities.
Good luck!
