"...Boiling water is cheaper than..." Especially when plain, hot, tap water will do. Doesn't have to be boiling hot. Firing a non-corrosively primed cartridge will do nothing.
"...PROPER cleaning and oiling was essential..." Only ever used non-corrosive DA and IVI(crap compared to the DA) ammo. Only thing the CF gave us to clean everything, MG's included, was regular motor oil. No other solvent existed in the entire system.