S&W 422 rear sight help

[mousegunner]

My BIL has 422 that has a loose rear sight. The groove on the top is wider than the sight so it moves side to side in the groove. At 10 yards it shoots a group about 3 inches wide. If you push the sight over every shot then it groups about 1.5 inches. I didn't have a way to measure the difference but you can see a gap.

I have my own ideas on a fix but like to hear other ideas. Granted it's not a target pistol like his 41 but groups get way bigger as you go beyond 10 yards.

 

[SecondsCount]

Is it metal or plastic?

If it is metal, I have fixed a few pistol sights by stippling the bottom with a punch, and apply some blue Loctite on installation.

 

[Bob3700]

Either material, I would use some bedding compound to secure it on the frame.

 

[mousegunner]

Thanks, I had thought of bedding or stippling the sight so I was on the right track.