Some of the recommended 30-06 loads specify a longer than normal COAL. That gives just a bit more case capacity.
But the short answer is, I don't think SAAMI maximum loads for the 270 are ideal. If you check the reloading data, most stop respectfully short of the 65K max. Since the propellant gas can't read the headstamp, loading 30-06 to 65 KPSI is as safe as loading the 270 to that level.
I have pressure measuring equipment, and generally run my 30-06 at about 58 KPSI.
