Our Old Testament Firearms HB-Series barrels produced in partnership with Hughes Ballistics are chambered in 5.56 NATO. This 16-Inch USGI Profile mid-length Barrel is machined from 4150 Chrome Moly Vanadium steel with a Black Nitride QPQ Corrosion Resistant Finish and Black Nitride QPQ Corrosion Resistant coated M4 feed ramp extension.
4150 has a 0.50% carbon content and is used for barrels that need to be tougher, have more strength, and higher hardness than 4140 or 4130 can provide. It's a little less common and takes a little extra effort to machine but produces the right results.
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Old Testament Firearms
Old Testament Firearms
Old Testament Firearms
