Peter,
For deposits that you're working on (around the forcing cone and under the top strap), I like to put my revolver in my bench vise inverted, (using rubber passed jaws), and I use an eye dropper to soak the carbon deposits really good, using the surface tension of the Hoppe's #9 to keep it in place. Then I walk away for 12 hours, come back and replenish any Hoppe's that may have evaporated. I come back in another 12 hours and pick at the carbon using a 223 case with the case mouth flattened into a makeshift scraper. Remove as much carbon that you can, and soak overnight again.it may take a few days, but this technique hasn't failed me yet. It takes very little work, I let the solvent do the heavy work. The key is to be patient and let the solvent work. Give it days, not minutes!

Lou

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NRA Certified Instructor & RSO