WHAT DOES BENELLI M4 OR BERETTA 1301 MEAN?

Marine Corps diagram of a subject-stripped M1014 The M4 was the main gas-operated shotgun made by Benelli. Its function is built about a wholly new style and design known as the "car-regulating gas-operated" (ARGO) method. The small-stroke design works by using two self-cleaning stainless-steel pistons Situated just ahead with the chamber to operat