I never had Ruger action screws loosening. About half-way on this video you can see how to tighten the action screws of the M77 MK II and Hawkeye, and like others have mentioned a little Loctite helps too. I just don't use it.
https://www.youtube.com/watch?v=8KGAYS91BDk

Last edited by Ray; 10/10/17.