I’ve owned half a dozen of these rifles in both .270 Win and 30-06. They are well built, accurate rifles. The rear hole spacing was .50” up to about 1955 then changed to .86”. Talley makes a base for the .86” rear hole spacing.

My most recent M50 was a .270W that I had converted to .375 Ruger.

_____________________
If it doesn't feed, it's junk.