Originally Posted by 1hole
"...it shoots less than 1/2" at 100 yards with factory loads 150grain spire point made by Weatherby."
If you're getting that you best stick with it. And buy up all that ammo you can get in case they change something in it later.
I have hand-loaded for many years and anyone who can shoot a 300 Weatherby Mag. into "less than 1/2" at 100 yards", and is looking for better, is not in the real world. If you would put in the years, and $ for learning custom loading, you MAY perhaps do better for yourself? This is doubtful.