Rear Iron Sight Issue?

Met with a fellow forum member today to trade my rear sight, he noticed that the sight block (?) was loose an crooked. I had not noticed, (sights been sitting in a box), but I'd like to figure out what's wrong. Neither of us could find a screw that might be loose, so perhaps someone could help. Thanks!!

http://i68.photobucket.com/albums/i5...e/DSC01998.jpg

It is be design. I wondered this myself with my bushmaster. Below is the Bushy FAQ but basicly they spring load it to ride on the one side as a way to provide a constant plane rather then trying to keep it centered.

You can get match sights they do not do this if you want.


http://www.bushmaster.com/faqs/afmma...aqid=&question=