Gun magazines have reported that both the ACR and the Sig 556 had nitrocarburized barrels - in fact, all ferrous alloy/steel in the ACR is. Too bad the barrel profile/weight and cost derailed the ACR as the material process specs are impressive.
I don't understand the Marketing Departments. I'd openly tell generically what was done. Nothing can be hidden from fellow engineers with lab equipment anyway. I'd search for and exploit anything that would separate my product line and the rest.
"One cannot awaken a man who pretends to be asleep..."
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