The screw that secures the safety selector on my 590 backed out on me while shooting and the safety selector flopped up and down without actuating the safety mechanism.  I tightened it down in the "Safety Off" position as a temporary fix since I use it as a HD shotgun.  (Loaded, empty chamber)  What fixes are available to secure the screw tight enough to properly use the safety, but not too tight or too loose?  Is there a replacement part?  

VangComp makes an all-metal enlarged replacement safety for the 590A1, but I'm not sure whether or not it fits the 590.

Short of that, you might be able to use Loc-Tite to secure the screw.


ETA -- Yes, the replacement safety apparently will work.

Linky

Scroll about halfway down.