I attempted to mount a speedbead to my dads 870 express. I noticed play between the piece that goes between the stock and reciever and the piece the sight screws to. Then when I mounted the sight, I noticed that the mount is sitting unlevel(about an 1/8" or more higher in the rear). If I try to turn the wedge screw to take out the play it aims down even lower. Without adjusting the dot, its pointing at the reciever a few inches in front of the sight.
Any suggestions, or did he just get a dud?