[Gary57]

I have a Mark IV Hunter and the front fibre optic sight has a very small screw
and every time I shoot even 30 rounds the front sight gets loose and when I shoot
even more the sight is ready to fall off. Ive used loctite blue and it still comes loose.
Help, what can I do????????

 

[cannonball]

Call customer service. They were very helpful when I had problems with my bolt stop pin on my Hunter.

 

[buster40c]

You might try a real small rubber o-ring on the screw. S&W Victory had trouble with barrel screw coming loose. An o-ring or a star washer supposedly worked for the problem.

 

[Frontiersman]

Try some purple Loctite.

 

[SGW Gunsmith]

I've completely given up on the factory slotted screws. Those screws include a blue thread locker that just doesn't seem to do the job. So, I find these "custom" torx screws work out much better.