Well my CrossFit Coach brought in his G34 that he had stippled.  I really liked it but  why pay someone to do what seems easy.  So I decided to do my G20SF.  I did all my sanding to remove the OEM texture by hand.  No electric tools used.  I did a few practice runs on a spare ar pistol grip and a Glock mag loader to find the size I liked.  The toughest part was the first touch - so scared I'd push through.  I started light and applied more pressure until I liked what I saw.  I am pretty pleased with the outcome.  I used a cheap woodburner from Lowes and I modified a tip to be more flat.

Nice work.  I've never seen that larger circular pattern before, but I like it.

Looks almost like fish scales. Hmmm, wonder what that would look like on a fishgill Glock?

Looks good to me. How is the function of the stipple ? does it grab good flesh ?

It will not be slipping any that's for sure.  I really like it.  I am going to do my Gen 4 G41 if i cannot trade it for a G34