Well the design is what it is.
I'm looking at a new bolt head not because of the thread pounding.
I'm looking at it because I might find myself shooting some 80+ year old ammo and I'd rather not etch the original bolt face if a primer leaks. Just a precaution.
Rifles have collectible value, so enjoy them, but take precautions.
I suppose they allow a little over-rotation in the fitting of the bolt head on the assumption that the bolt head and bolt face will take the pounding once the threads loosen up a bit and get out of the way![]()