First, if you haven't, you need to read a couple of manuals. Not the load data, but the "how to" section. Hornady, Lyman, Nosler, etc. Find one that you "get" and keep it handy. Follow instructions. If you know a seasoned handloader, let them eyeball your work or assist the first time or two. I hope that wasn't hashing something you've done already, but you said "newbie".
The books are full of load data for many cartridges, and powder/bullet combos. Find what works in your gun.
300WM: 180gr SP, 76grs R-22, WLRM primers. Or 74grs R-19 same bullet and primer. In a 24" bbl, should get near 3150fps. Can't say it will be accurate in your gun or not. R-22 is a fine powder in the 300WM. Good luck.