RE: Win. Mod.70 per 64 action
Biggest difference in the pre 64s have controlled round feed, meaning that the case is held by the bolt the moment it is released from the magazine (like a Mauser or most Savage's I have seen). Winchester built a few more just before the New Haven plant closed.
A push round feed (like Remington 700s and Browning A Bolts) litterally push the round (which is free) into the chamber.