Barrel steel, steel coatings

So I plan on shooting my current Colt HBAR (chrome chamber, naked bore) barrel until it gives up the ghost.  However since I plan on shooting after that point I have been researching what barrels are out there to replace the one I'm using.  Considering that the cost of parts only goes up it makes sense to buy high wear parts and stock them for the future.

High power shooters choose stainless steel barrels and that is that.  I don't know of any high power shooters who don't.  I'm the odd duck on the line who is shooting a CMV barrel.  So that narrows down my list of barrel choices.

Krieger barrels start at over 400 just for the naked barrel.  A White Oak barrel made on a Wilson Blank is about half that.  Is the Krieger twice as good as the White Oak?  Maybe, but I don't think so.  Noveske is about the same price as Krieger, but once again I'm not a good enough shooter to know the difference.

Stainless steel barrels come in a couple varieties that I can find, 416 Stainless for the major brands, and 410 Stainless for Bravo Companies stainless barrels, and LW50 for yet other companies.  The "better" the steel the more expensive the barrel (generally speaking).  Straight 416 has the lowest life expectancy, only slightly better than uncoated CMV.  416R, which has a lower sulfur content than regular 416, seems to last folks about twice that of CMV.  410 and LW50 seem to start losing accuracy about 3 times that of uncoated CMV.

On the CMV side of the house, there are two alloys that come up, 4140 and 4150.  The only difference is a small bit of carbon in the mix.  As far as wear and tear goes, I can't find any significant difference between these two steels when they are uncoated or coated in the same manner.  That doesn't mean differences don't exist, only that I can't find them.

Steel coatings, traditionally for the AR world has meant chrome.  A chrome bore and chamber has been a staple offering for reliable rifles the world round and the AR is no different.  However chrome makes accuracy a crapshoot, either the rifle shoots good or it doesn't.  And there is no way to tell which barrel will survive the chroming process with accuracy intact.

Now a "new" process has hit the gun world, nitriding (aka Melonite) which allows better dimensional stability in the final product than hard chrome plating.  The Smith and Wesson M&P 15 series makes good use of melonite coating on their barrels to good effect.  Life expectancy of a melonite coated barrel is as good as if not better than the best stainless steel barrel.

So there are options out there other than stainless.  However melonite coated 4140 or 4150 barrels in a Service Rifle contour are pretty much a custom order at this point, so it looks like I'm going with stainless for now.