What is the proper method and sequence to tighten the action screws on a Ruger M77..??..

I don't know about proper, but in the case of the Ruger (and because of the angled screw) I use center, front, rear. Seems to work OK. FWIW - Dan

You may get lots of different opinions on this one, but I would tighten the front screw then the rear, and finally the middle one. Be sure not to over tighten the middle screw. Doing this helped the groups on a couple of Ruger rifles for me.

R F

IMHO, the correct way is as stated above. If the action is properly bedded, the the front, rear, middle. Just snug the middle, don't tighten it with a breaker bar.
I think some of the confusion about this is that some rifles are not bedded correctly, and by loosening the rear screw, for instance, when the action is setting off the stock's bedding surface in the rear tang area, will take pressure off the action, removing the flex, and actually make the Ruger shoot better. Then someone get the idea this is the way to go with all M77's.

Thank you all very much....