I am using the Williams sight on a Marlin 39A. I changed out to a .050" aperture. I would like to go even smaller. Any idea if there is one? I have also seen some Anschutz adjustable ones. I don't know if they are legal and if they will fit the threading.

Joe

All these from Merit Optical are excellent with continual adjustment of the opening.
http://www.meritcorporation.com/products.html
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