While the STW is certainly a player in the long range arena, I chose to take a different approach.
I have a .300 WBY, necked down to .284, with a 35 degree shoulder and a .312 neck.
Before I left for Alaska, I did a real quick ladder for load development.
With the 180 Berger, I am at 80.5 gr of Retumbo, and 3200 fps. Accuracy is about an inch at 300 yds. I've been using .003 neck tension. I'm about two grains from max, and should top out at about 3300 fps with the 180 Berger. 9 twist 28" barrel.
Advantages to my approach... better brass, slightly more velocity.
The shoulder is darker as a result of annealing.