by Warrigul » 24 Sep 2014, 5:32 pm
It is quite interesting the whole copper vs ammonia subject.
Whilst the barrel makers don't recommend excess usage of ammonia as a copper solvent in stainless barrels, in my trade I have seen precision stainless(of all grades) parts immersed in pure ammonia/anhydrous ammonia/ammonia and oil, both hot, cold and air/ammonia mixes and have never encountered any pitting or degradation.
Anything that changes the colour of copper residue involves a chemical reaction and is in the same line as ammonia regarding stainless.
I clean my stainless barrels with ammonia solvent and whilst I never soak them am not overly worried either.