I have had my brother do a few of my guns with a hand-rubbed linseed-oil finish that is deep enough to dive into and drown. He usually sheens the final coat down with very-well-used 0000 steel wool with baby oil to take the high-gloss finsih down to a beautiful satin (actually he does that between all coats to ensure an extremely smooth finish - feels like silk). The finish is extremely durable and with proper care will last my lifetime.
All the teflon pans I've seen were pretty fragile with regards to the coating staying put. There's a reason they all come with warnings to not use any metal untensils on them. I imagine it would fall right off an even moderately used gun.
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