BigClubs, it is something akin to ‘THE SHADOW’. “WHO KNOWS!!?” “WHAT EVIL LURKS ...etc.,” I don’t, BUT! The 308 W is shorter than the 30/06, the 308W is larger in diameter but shorter than the 30/06. The 308 W has little trouble keeping up with the 30/06 when both are shooting 150 grain bullets. Then there is that part reloaders have so much trouble getting a grip on, the WSM case takes a beating when fired, again, the WSM is larger in diameter and and shorter, meaning the case takes a beating, or gets a hammering from the inside out when fired. Back to the ever present question, “I can not size my WSM cases, no matter how much bumping I do I can not bump the shoulder back, what must I do? The number one answer has to do with bump and bounce, a no win condition.
Then there is the Chinese (finger) hand-cuff principle.