Early Ruger M77 with the tang safety locked the bolt, as I recall, with the safety engaged. Later ones allowed the bolt to open when engaged. Can a 'smith fix newer ones to lock the bolt?

the mkII are 3 position safeties, that block the trigger and then block the bolt

pull it all the way back, and it is an obvious lock on the bolt.
jeffe

Thanks, I understand that, but my interest is in the M77 with the tang safety, not the MkII.

okay.. i thought you meant tang and mkII ..