The .250 AI is a ballistic twin to the .25 Souper, for all practical purposes at least. While it is a fine cartridge, it didn't set the world on fire as a wildcat like the .243-08 did. The factories look at shooting trends and will adopt popular wildcats (.22-250, .225, .243, .244, .25-06, .260, 7-08, .338-06....). If the .25 WSSM is
too much cartridge, why not load it down?
I assume that Greywuuf shoots a .256 Magnum in his Contender, rather than a .257 Weatherby.....