Couple of interesting things concerning cleaning.
First, Armalite published a series of bulletins (they may still do) about tips and tricks for their weapons. In one case, SF embedded with tribesmen in Afghanistan noted with our supplied M10s/M16s/M4s or even AKs, no one was going to spend large sums of money on expensive Break Free. Armalite recommended automatic transmission fluid to clean, and motor oil to lubricate. The tribesmen did just that using knotted up bootlaces to clean the bore.
Second, during the Gulf War, I noticed SF units were using a dry powder lubricant rather than even a light coat of oil which attracted all the damn fine sand. It seemed to work out as long as they used it routinely and never went back to oil. Never heard of what happened to that substance since. To me, it had the consistency of talc.