Hi,
When someone posts a method and implies it is "THE" way to do something, be skeptical. There are always multiple ways to do any task and meet any objective. I also wish that folks describing their favorite stains and finishes would post photos of their work. That way readers can judge if the methods fit their needs. I've used many different finishing products over the years but homed in on 2 based on my experience. Both use tung oil. The first is 25% raw tung oil, 25% urethane varnish, and 50% mineral spirits. I used this mix while living in SE Alaska because I could not easily get polymerized tung oil, my favorite finish, and developed an excellent alternative that was more readily available. It stood up very well to the harsh conditions of rain, salt air, and sea spray encountered during hunting in that environment. My second and favorite finish is Sutherland-Wells polymerized tung oil. I use it because it can match the appearance of any original finish, which were mostly linseed oil and copal varnish mixes, but has superior weather resistance to linseed-based finishes and it does not darken over time. Tung oil is ancient and was sometimes referred to in centuries past as "China" oil. I doubt 17th-19th century European and American gun makers ever used it. They used linseed oil, not because it made a great finish, but it was cheap and available. There is also evidence from some Lehigh Valley rifles, that some gun makers sealed stocks first with shellac and then applied linseed oil varnish on top. Anyway, I substitute tung oil for linseed because it has superior qualities and I can make its appearance match any of my objectives. Every stock I finish is a different story because of the serendipitous nature of wood, the species of wood, and my objectives for the appearance of the gun. Sometimes I apply just the finish, sometimes I tint it with oil soluble dyes or alkanet root, some times I apply the finish with sandpaper to create a grain filling slurry on the surface, sometimes I apply a few coats for a low sheen, and sometimes I let finish build up so I can rub it back with rottenstone and create the glassy smooth finishes found on Purdeys and Holland & Hollands . Each stock is different.
dave