Barrel nitriding residue removal/solvents/toxicity

[crazymoose]

I know barrel nitriding has been a pretty contentious topic around here in the past couple of years, but I couldn't find anything about this particular aspect of it.

I have a couple of nitrided barrels that I need to clean of the residue left from the process. One just has some gunk in the bore, the other has pretty severe gunk in the bore, as well as residue on the barrel indexing pin and actual salt crystals formed on the ring-shaped "nook" between the end of the barrel in the extension and the interior sides of the barrel extension.

Question 1: Any cleaning agents or solvents recommended for residue removal?

Question 2: The chemicals used in the salt bath nitriding process are some pretty nasty shit. Should I assume that this residue is equally toxic? Any special precautions to take when cleaning, and to make sure that all traces of the stuff have been removed?

Thanks for any advice.

[Col_Crocs]

IIRC, constructor touched on this topic in the old thread. You might want to dig it up or perhaps message him.

[tom12.7]

I've seen some guys scrub it out in a hot bath of 5% IPA with a few drops of Dawn dish soap, I don't know if thats best though but it seemed to work OK.

[EzGoingKev]

India Pale Ale?

[constructor]

I know barrel nitriding has been a pretty contentious topic around here in the past couple of years, but I couldn't find anything about this particular aspect of it.

I have a couple of nitrided barrels that I need to clean of the residue left from the process. One just has some gunk in the bore, the other has pretty severe gunk in the bore, as well as residue on the barrel indexing pin and actual salt crystals formed on the ring-shaped "nook" between the end of the barrel in the extension and the interior sides of the barrel extension.

Question 1: Any cleaning agents or solvents recommended for residue removal?

Question 2: The chemicals used in the salt bath nitriding process are some pretty nasty shit. Should I assume that this residue is equally toxic? Any special precautions to take when cleaning, and to make sure that all traces of the stuff have been removed?

Thanks for any advice.

I've had barrels melonite treated since 2008, thousands of them. The outside and bore is rinsed at the place doing the treatment but the threads when covered with the barrel extension can not be cleaned. From 2008 until Aug 2013 I removed the barrel extensions and cleaned the threads without any kind of protection. A rag and brush covered with that stuff was in my hands most of the day. I've always been bad about saying "well, it hasn't killed me yet".
I can still say that...yet. I have low level cyanide and lead poisoning after cleaning over 10,000 barrels. I'm not sure the lead came from the barrels, it could be from anything I've been exposed to in the last 25 years of working construction or welding or whatever. It may not be a bad idea to wear gloves and wash your hands after cleaning with any chemicals.
PB Blaster is a good solvent used to free rusted bolts and nuts. It does a good job of dissolving the residue left on the barrels. Hoppe's #9 is another.
IMO you don't want to clean any barrel to the bare metal, that little bit of residue left in the barrel keeps dry metal from collecting copper from the bullets. It helps reduce copper fouling. Run a brush dipped in #9 or PB through the barrel 3-4 times from the breech. A patch of alcohol to remove the strong solvents. A patch with a thin oil, then a dry patch to remove any excess oil.