You will see reports all over the place for the 300WM with 215s. I have had one with a 27" and one with a 28" barrel. Both allowed seating the bullet above the NSJ. They pushed the 215 2890 and 2950 respectively. Some get faster but I would not build a custom expecting something that may not happen. The problem with the WSM is twofold. One is some guys are shooting them in short mag boxes and often short barrels with powders not really well suited for the cartridge. The second is guys who I trust their data more are looking for a node good enough to win but not too fast to induce unnecessary torque and most often use looooong barrel. I will say that there is no doubt the WSM will be more efficient. On average it is going to loose 100 FPS to the WM with both set up the same.