Well, let's see. Only two?
OK, the 30-06.
Oh, TWO. OK, the 30-06.
Good thing I have 2 30-06
I can see some merit in this. Set one up using lighter 130-150 gr. loads and the other 180-200 gr. for example. Or one with a frangible cup and core and the other a bonded or mono.
Another thought would be to set both up for the same load depending on the game hunted. That way one could be primary and the other a backup.