I have a 20 year old Win 70 post 64 in 222 remington. I would like to rebarrel it in 6/284 but currently have a head size of .378 on the bolt face. How can I get this changed to .473? I looked at the Winchester web page. According to the web page, this has to be done in the factory. Then they say it has to be appropriately functioning prior to shipment. Well, if the bolt face doesn't match the chamber it sounds like they won't do the work. Or, they will try to make me buy one of their barrels in an appropriate chamber. My father tells me you use to be able to just buy a new bolt. What has been your experience? Am I stuck?

The bolt face on you M70 can be opened up,the extractor changed, and you will need a new magazine box, follower, spring, and to shorten the bolt stop.

Any good gunsmith can do the work. Winchester has sadly been overrun with lawyers and they don't want any liability issues. It's a shame, they used to be quite responsive to customers.