Never had this happen to me, but my guard screws get fiddled with at least every couple of years. If you wanna loctite them, use blue 242 or purple (don't know the number) and you shouldn't have much trouble removing them.
Had that rifle been shooting okay?
I'm here to give and receive knowledge, not affirmation or adoration. If you don't like it, mierda dura
. Intellectual honesty is not for fragile egos.