I am skeptical that that is the main mechanism. In fact I am skeptical that any ammonia in Robla Solo Mil has much effect on copper, as it will have been neutralised by the nitric acid content, forming ammonium nitrate. Agreed, this could encourage rust and pitting if allowed to dry out on the bore.
The copper dissolving properties of the stuff seem likely to me to be down to the nitric acid. Nitric acid is unusual amongst acids because it will dissolve copper, when even in dilute form, creating copper nitrate. It also dissolves lead. Just as ammonia reacts with copper to form copper nitrate (the blue colour you see on patches). I can see that this will make it an effective barrel cleaner.
I think that the selenium dioxide will form selenous acid in the concoction. But I'm not sure what effect that has on metal fouling, more research required.
In fact typical gun cold-bluing solutions are a mix of selenous acid, copper nitrate and nitric acid. Which seems to be pretty much what Robla Solo Mil contains, which is interesting. Along with other secret sauce. Perhaps you might even end up with a cold-blued barrel interior after using it ?
Ammonia solution (ammonium hydroxide) is a good copper and zinc solvent, and despite rumours to the contrary, is unreactive with barrel steel in the percentages found in typical barrel cleaning formulations. Lilja barrels mention this specifically at FAQ - Lilja
Apart from its smell, it is probably the perfect solvent for copper and zinc bullet jacket metals.
In fact Lilja recommend Butch's Bore Shine as their preferred cleaner, and Sweets 7.62 for heavy copper fouling because it has a particularly high ammonia content, 5% or more.
Centerfire Maintenance - Lilja
We recommend that your new Lilja rifle barrel be properly broken-in to obtain the best accuracy. A proper break-in will help ensure that your barrel will clean easily in the future and that you will achieve maximum accuracy potential. Please follow these important instructions.We are concerned...
riflebarrels.com
Sweets MSDS:
FWIW one of the active ingredients of KG12 is sodium cyanide, forming hydrocyanic acid when dissolved in water, a copper solvent. KG12 is over 90% water. Although seemingly an eco water based thing, it does have some hazards. And I would suggest should be followed by e.g. oiling the bore afterwards to displace any water and protect against rust.
From their MSDS:
Any
