I was supposed to sit around camp to keep grizzlies away from the cook and her kids. It's a problem every year there. Due to a shortage of guides, I helpd out where and how I could by guiding a fellow in about the same decrepid physical condition as myself, so we managed quite well, although it was trying at times.
: Metaloy isn't something you can do yourself. It is a process done by some plating buisinesses.
: The rust must be cleaned out - which isn't a problem. There are products on the market for removal of rust and straight old gun solvent an 4-OUGHT steel wool on a brush works well enough.
: Most plating is a coating on top of the surface that will put a .001" to .003" surface film on the metal you are having plated. In this case, it will make the bore & chamber smaller in diameter. This may or may not be a good thing, depending on bore & chamber size size already. If the chamber and bore are already at the 'correct' size it is possible a .004" tighter chamber won't let you chamber a round and .004" tighter in the bore (1 thickness is .002" for expample X 2 = .004" total thickness) may mean special sizing dies or reducer dies for bullets. On the other hand, many of these guns had generous chambers and might benefit from such a coating. That is the mistery and can't be pre-judged unless the person you purchase from knows all the numbers you need to proceed with this. One must know what one is about here or one might get into trouble.