I shot up a bunch of old cupro-nickel jacketed bullets in a Springfield one time long ago. I experienced severe jacket fouling. Following the old timer's protocol for removing it, I filled the bore with stronger ammonia (the Real McCoy) and let it sit for a while. When I un-stoppered the barrel and dumped it out I got a good whiff of the ammonia fumes and passed out. My wife dragged me away and I revived ok. Lesson learned: don't pull that trick in the bathroom, and wear a respirator. :D

Oh, it did a swell job of removing the cupro-nickel fouling. (I did start passing up on the cheap WWI surplus '06 ammo at the gun shows after that.)