Quote Originally Posted by sharpshooter View Post
Well, first of all this notion that something bad will happen after 15 minutes is total BS. Ammonia is a base, not an acid. It will do nothing to steel. The fact is that if you apply Sweets with a patch, in 15 min. it is totally spent and has dissolved all of the copper that amount will do, and now is just evaporating. By the time you push a patch through the throat, you have essentially wrung most of the solvent out of the patch, so now it is not even really "wet", just moist. Most of the blue comes from the ammonia working on the brass jag because it has the most surface area. Once that "moist" patch is pushed through the bore, it only takes a matter of a few minutes for it to evaporate, giving the "less than adequate amount" of solvent enough time to just clean the tarnish off the copper fouling before it is expended. If you fire more shoots at this stage, the copper fouling will only get worse, because you have essentially "fluxed" the remaining copper and subsequent firing will make the copper fouling adhere easier.
Let the solvent do the work! Put enough in to do the job. Don't use a brush, or a patch, use a MOP. Make it sopping wet as it can be. Let it set for 15 minutes,after that, it's not dissolving anymore. Then push it out with a patch and do it again, or maybe more if it's not gone yet. If it's bad as yours looks, plug it at the chamber and fill to the muzzle. In 2 days , you will push a big blue goober out of the end.
Once you get all the copper out, if you notice any pitting, it was caused by galvanic corrosion, not by solvent. Galvanic corrosion occurs between the copper fouling and the barrel. Copper solvent only reveals what is underneath once the copper is gone. That's why it's important to stay on top of copper fouling.....the longer it sets with it, the worse the corrosion.
This makes good sense, and possibly the carbon laying between the steel and copper layers might add to the corrosion too. I did some quick research and found this article: http://www.worldstainless.org/Files/...h_Other_EN.pdf

See page 12 regarding using copper fittings on Stainless Steel pipes and tell me (us) what your thinking is. I'm no metallurgist so I'm genuinely interested. I've not done my best to rid my barrels of copper during each cleaning, so I may be missing the boat by no doing so. I do use a camera to look inside so I am able to confirm my cleaning methods will get it all.