The link Dave provided is a good one.
I did my first and only so far gun with Permalyn sealer. I followed Bill Shipman's method in that link.
However, when I put on each coat of sealer as finish after the first sealing coat, I put it on too thickly. After 5 or 6 coats, it was far too built up looking. I think the key is to do very very thin coats or wipe it off after applying each coat.
I tried rubbing it back with rottenstone, oil, and a toothbrush, but I didn't like the result very much. It was hard for me to get the finish even and just the right amount of rubbed back.
So, what I did in the end because it still looked too built up, was I rubbed it back to wood as much as possible with maroon 3m. Then I hand rubbed in a total of 2 coats as someone else in that thread suggested. That worked superbly. It gives a nice satin appearance that I don't think looks plastic at all.
Also, you'll notice that if you watch Kiblers video where he finishes a woodsrunner with Permalyn, he puts on each coat using a 3m maroon pad and wipes off the excess so that it is a very thin layer being applied. And Kibler obviously knows what he's doing.
For more information on Shipman's method, you can search Permalyn on the ALR forum by the user Ed Wenger. He builds some beautiful guns and uses Permalyn. He uses Shipman's method for the most part and explains it in a couple of threads.
Here's mine with Permalyn
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