Melonite, nitride, etc provides better corrosion restitance than bare stainless steel or chrome plating on a chromemoly barrel.
I would call it closer to nearly rust proof. Like John said however, there is a slightly different process for nitrided stainless steel than for chromemoly. If improperly done, nitrided stainless steel can have poor corrosion resistance. When stainless steel barrels are nitrided properly, the finish provides greater corrosion resistance over bare stainless steel.
If you want a high quality nitrided stainless barrel for precision shooting, shop carefully as there are a few side effects to the nitriding process that can have a negative impact on precision if the barrel is not preped' properly prior to nitriding. If you are thinking of having a stainless barrel sent off for nitriding, shoot it only a couple of times at the most, no more, but do not send in a brand new unfired stainless barrel. Or, if you dare, use some lapping compund on the bore and chamber before sending it off. If you are buying an already nitrided match stainless barrel, make sure you ask if they do any special preperations to the barrel prior to sending it off to be nitrided. Most people doing nitriding on match barrels are not putting in the extra effort needed to gain that top performance.
Last edited by chicoredneck; 09/27/12.
