Tim50,
I have a pre 64 M70 fwt in .308 Win. The magazine is blocked and the bolt has a bolt stop to shorten the throw. So it would appear that the 30-06/270 is the same length action as used on the 308/358 chambered rifles. I have a .270 Win pre 64 fwt arriving (from the US) any day so will be able to confirm it soon.
Regards,
Magnum308