416R Stainless steel is used extensively by manufacturers for their match grade precision barrels. It is the highest grade of stainless steel available, specially formulated to function in Arctic cold conditions down to -40 F.
416R stainless is ideal for machining very precise and polished rifling, chambers, and crowns into the barrel to maximize consistency and accuracy potential. 416R stainless barrels may not match the longevity and toughness of 4150 CMV barrels.
4150 Chrome Moly Vanadium steel is the proven military specification steel type. The barrels in M4 carbines and M240 machine guns are constructed from 4150 CMV steel.
It is difficult to produce a 4150 CMV barrel offering the same accuracy potential as a 416R stainless barrel made using the same manufacturing techniques.