This 5.56 chambered 12.5 inch Government Profile
Modern Series Barrel is machined from 4150 Chrome Moly Vanadium steel with a
QPQ Corrosion Resistant Finish and QPQ coated M4 feed ramp extension.
4150 Chrome Moly Vanadium
QPQ Corrosion Resistant
Gas System Length
Gas Block Journal
(QPQ) Quench Polish Quench
is a specialized type of nitrocarburizing case hardening that
increases corrosion resistance. It is sometimes known by the brand name of
Tufftride, Tenifer or Melonite.
(QPQ) is a huge improvement over Chrome Lined barrels. Unlike chrome
lining, where the chrome is built up on the surface, QPQ converts the surface
without the risk of dimensional build up.
(QPQ) is used
when two or more of the following properties are required in a work piece: