According to the article, this new developmental machine gun comes in at about half the weight of the M-2. Where the M-2 weighs approximately 120 pounds, the XM806 weighs just over 60 pounds.
The XM806 also has 60% less recoil than the M-2 and has made changes in the way barrels are replaced. An unidentified Army official said:
“Safety is improved through a manual safety and a quick change barrel that eliminates the requirement for the operator to adjust headspace and timing,” Army officials added. “The reduced recoil permits the mounting of an optic for greater lethality through increased first-burst accuracy and control.”
The article makes clear that the M-2 is not being retired. Rather the XM806 is an effort to bring that same long range firepower to light infantry and special operations units.