I had problems on my current chassis with the action screws coming loose, once during a match. Ticked me off so much I bedded the lug and used blue lock tight on the action screws. Solid as a rock now. The only minor draw back is when you have to take it apart for some reason, you really should try to clean out all the lock tight residue. No big deal to do.
The reason I always pillar bed (Not just Bed) is to prevent the action screws from loosening. The pillars need to touch the action and the floor metal to prevent the stock from being compressed and allowing the action screws from loosening. The bad thing about this is that when you re-torque it applies uneven stress to the action and may cause a shift in the POI or worse, the accuracy
If you have a metal to metal to metal pillar bedding there will/should be no reason the use a thread locker. I have checked action screw torque on rifles that have not been taken out of the stock in many years and the torque remained the same.
Before I started adding pillars to my bedding, loose screws were common. (In the rifles, I still have a few).
If you have a rifle that has this issue, a non hardening thread locker is OK if you use it sparingly in my opinion.
I find actions that are metric and use 6mm X 1.0 threads for their action screws tend to work loose themselves through use of the rifle and transportation of the rifle, even when pillar bedded and properly torqued. The tread is just too course. Thread locker is a must on those, IMO. There is a reason most gun screws are fine threaded.
morning, doing this fix for years. first I change the stock
screws to flange base torque head screws, second I put
the bevel washers under the head of the screws. go to a
reputable fastner place to get the hardware.
justme gbot tum