With 30-30, 308, 30-06, and 300 being allowed, it's not a hard stretch for them to allow in 7.62x54R, and .303 British... Would let some of us surplus guys in on it too. Of course then they'll end up with a huge list of allowed calibers... Might as well just set diameter and case length requirements like they've done already. If not you'll have the constant requests for evaluation of all the calibers in between what's already allowed in terms of size and power...
And 7.62X39, and 7.7X58 Jap...