Re: How to remove devcon from barreled action?
I've used fine steel wool to remove JB Weld from bluing many times with good results and absolutely no harm to bluing. I've also used a steel wire wheel to remove burnt on carbon without a scratch on the finish. How do you think red rust is carded off when you apply bluing? A toothbrush? I should mention I'm using actual steel wool, NOT synthetic steel wool. That stuff will tear through tool steel. Synthetic wool contains abrasive particles that are much harder than steel, probably alumina or something similar, so it's closer to sandpaper in that sense.
I apologize if I'm incorrect here, but my experience just does not jive with what you guys are saying. Granted, Devcon is probably a fair bit tougher than JB Weld, so I can't speak directly to how well that will remove. But fine steel wool shouldn't easily damage a quality bluing job.
Edit: Another method I've heard of is using a copper penny (1964 or older) to scrape the substance off. Of course, since copper is so soft, it shouldn't harm the finish.