I have always been told to push back into the rail slots when installing the rings. It makes it so that recoil does not have any room to push the rings backwards.
Maybe that's wrong, just what I have been told.
Some rail mount rings have what the manufacturer calls a "recoil bar" Short steel bar the fit's in the rail slot. They say to push the bar/mount forward against the slot. Recoil pushes back and the bar being tight against the rail it well not move.