>Ammonia can make metal more prone to stress cracking. Don't use it.
Even stainless??
Well I have some simple green and vinegar around the house so I will experiment next time.<
Here's the skinny on this one: ammonia in reasonable concentrations, and for short periods of time, will not hurt your barre. However, if it is going to hurt your barrel, stainless is more susceptible to the effects than regular steel like 4140. This stuff about ammonia hurting the barrel was bantied by the people promoting Moly'd bullets, so as to make the reduction in copper fouling that came with Moly'd bullets look better. Too much junk science and not enough real science, and most of it based on insufficient sample sizes for testing to prove anything real.
A good brand of household vinegar is a bit much used straight. However, dumping vinegar into windex containing ammonia only serves to cancel each other out. A Simple Green solution with a small amount of vinegar will do no harm.
I use Ballistol Milk; that is, 2 parts Ballistol to 8 parts of distilled water and it works very well, indeed.