Loose sight

[Omega]

I have a problem with rear (Novak style) sight on my new DW Patriot Marksman. It getting loose after 20-30 rounds. How can I make it stay in place? In the same time I'd like to have opportunity to resight if neccessary.
That little hex screw in the sight does not hold it place and without this screw - sight goes left and right on its own
Also I am wondering if someone can recommend me good gunsmith in Twincities, MN area.

 

[Old Fuff]

A gunsmith can remove the sight, peen the dovetail closed a bit, and then replace the sight. It should be tight enough so when the screw is set the sight won't move.

 

[Walt Sherrill]

Remove the sight and using a pointed punch, make a few dings in the bottom of the dovetail.

(The center of the spot punched will be lowered, but the surrounding area will be raised slightly, causing a tighter fit.)

That's probably what the gunsmith would do...

 

[Westvagunsmith]

Walt has the right idea, this is how I would address the problem.