I recently purchased a M-4 type Bushmaster and notice the rear sight assembly, although functioning properly, stays slight cocked to one side(the left) when in the full down position.
In other words the left side of the sight is in contact with the carry handle, but a slight gap exists on the right side of the assembly. It seems to be caused by spring tension, because if I push it back to center, after a couple of shots it returns to its slightly off center position.
I notice there appears to be a ball bearing on the left side of the sight where it contacts the carry handle.
It has not affected the zeroing of the weapon and may just be the built in tolerance of this sight assembly.
Is this normal in your view, and should I be concerned?