My rear sight came loose at the range.  A friend had some allen wrenches and we tried to find the right size.  The set screw had never been touched since I bought it new.  We could not get a wrench to fit.  I took it home where I have dozens of allen wrenches.  I could not get one to turn the set screw.  Evidently they reamed it out when they installed the sight.

The rear sight comes out easily.  I thought it would take a decent amount of pressure to move it, but not so.  It also had some brown gunk under the sight.

I know the set screw is a problem, but is the other stuff kosher?  Sight that slides to and fro easily and brown gunk?

send it back.  i've shot approx 900rds through my loaded and everything is still tight.  everything except my groups anyway.