I have a Glock model 22 on which the rear sight moves within the rear sight grove with minimal pressure. I have never had this problem with any Glocks or this Glock firearm itself. I first noticed the rear sight move when I was putting my shooting gear in my trunk and the Glock slid out of its case and landed near the edge of the trunk, it only fell two to four inches and did not land on the sight. I noticed right away the sight was off to the right of center and when I put little pressure on it to the left it moved very easy. Do I need to get the rear sight replaced or can it be fixed with a rear sight mounting tool?