Thanks. So it would not be good for defense guns that are left loaded.I know this for a fact as I had a 45-70 custom snap cap made and left it in a chamber that was wet with Ballistol. I forgot about it and after several months found the plastic retaining plug in the top of the unit had popped out along with the spring. This snap cap had a hard roll crimp holding this spring and plug in place but the Ballistol actually attacked the brass leaving the case mouth so thin that the spring broke free.
That is one instance but I have since found that brass cases left in a cylinder wet with Ballistol can be compromised at the case mouth. I have pulled bullets and found the edges of the case mouth almost razor sharp from corrosive attack. Actually if you let some brass set in Ballistol a day or two you will see that it becomes very shiney which in essence is the product etching the brass.
Anyway Ballistol is a great product but can and will attack brass.
While not the best thing to do, I have over the years just sprayed guns down with Rem oil, let it dry and reload.