Hodge Defense 16? 5.56mm Carbine Barrel is the barrel used on the Hodge AU Mod 2 rifles. Incorporating FN’s proprietary steel (the same steel used in the M249 saw), these barrels were designed and made to Jim’s specifications and optimized for the M855A1 EPR ammunition, which is far more demanding on barrels.
M855A1 rounds operate at about 62,000 PSI (over 55k from M855) and are designed to perform to an expected standard of terminal performance and barrier penetration over a broader range of engagement distances, previous ammunition was criticized for being unstable and not providing consistent performance outside of a narrow optimal range.
The AU Mod 2 is optimized for running M855A1 EPR, and this Hodge barrel is at the heart of the system.