Some say it's the amonia, others say it has no effect, and it's just that you scrubbed it out with a water based liquid cleaner. I say that Hoppe,s #9 has been doing the job for me for many years. Corrosive ammo or not. I just do a much more thorough cleaning with repeated scrubbing after corrosive ammo.
Cheapshooter's rules of gun ownership #1: NEVER SELL OR TRADE ANYTHING!