Check this site.
http://www.shooting-hunting.com/resu...hs&FoundID=225
and I, too, have a story.....
I took a misbehaving shotgun (failed to eject spent shell) to a "gunsmith" in Hawthorne Florida. He decided that a certain, fairly costly part had to be purchased, and asked me if I agreed to that. I said "Sure, if it will do the job". He then stopped in his tracks, frowned, and said that since I questioned his decision, he wanted nothing to do with the job, handed the shotgun back to me, and told me to leave. Anyhow, I sent the shotgun away to a smith I found on Accuratereloading.com ....and he simply changed the position of a tiny part in the gas system. The gun then worked perfectly.
When in the Hawthorne shop, I should have smelled that coming. Before we had even started on the subject of my shotgun, he picked a REALLY pitted, buggered Luger frame off his bench, and proudly showed it to me, as his latest "score".
Incompetents are everywhere, as well as (it seems) some real nut cases.
There is a wonderful gunsmith (Dennis Olson) in Plains, Montana (at 500 Main Street, I think). If (literally) my life depended on the quality of a certain gun project.....he would be the one I would talk with.