S&W 686 3 w/4 position front sight

[Bigbubba]

I bought this used from another CGN'er....didn't get a manual.
It has the 4 position adjustable front sight.
I cant seem to get it to move, dont think there is anything wrong with it but I dont want to break it either....so, what is required to change the sight to the next position?

I can add a pic later if that helps.
Thanks
Marty

 

[Casper]

Push down on the rear of the sight as you turn the dial, the sight is spring tensioned.
and the tiny hex screws on the top are for adjustment up or down in each position.

 

[Bigbubba]

Thank you