The Beginnings
The dual gas piston idea was not at all original with Benelli, not even close. Mossberg had it in 1977, it was awarded in 1978, predating the Benelli M4 by over 20 years. It is patent# US4102242A. Since 1999, the Benelli M4 Super 90 has been the M1014 Joint Services Combat Shotgun with an 18-1/2 inch barrel, designated as the “M4 Entry” with a 14 inch barrel. The Cerakote non-collapsing stock civilian version currently sells for about $2000. In military trim, it weighs about 8-1/2 lbs., about 8 lbs. for the civilian version.
The original M4 models had two gas ports. However, the ARGO system isn't completely “Auto-Regulating Gas-Operated” as advertised. The 2 port barrels were quickly dumped for civilian sales in favor of the 4 port barrels, Benelli saying that the “M4 features a modified gas system designed to function with light tactical loads.” What constitutes a “light tactical load” is unclear. It was also called the M1014 (Low Recoil) for a time. While they were better at cycling low recoil and trainer type loads, they also had impressive failures when using heavy loads. Apparently, now, the 4 port barrel misadventure is over and only 2 port barrels are made. In one test, comparing Federal slugs the Benelli averaged 35 fps slower than the other common semi-auto shotguns with barrels of the same length.
In the twenty years since the M4 was designed, not much has happened except for the unfortunate misadventure with the 4 port barrel. Nothing was ever done to introduce an ARGO shotgun that could be rationally used for general hunting and clays purposes. Nine years ago when the pre-Vinci hoopla began, I mused that perhaps, finally, Beretta-Benelli was going to do something mainstream with the ARGO system, but that was not to be. As we all know now, it was the Vinci.
Remington improved on the basic A.R.G.O. Action of 1998, patenting their own action and their “VersaPort System,” and it has been released for some time now as the Remington Versa Max 3-1/2 inch chambered gas-operated autoloader. The Versa Max action was designed by Gian Mario Molinari of Italy, filed for patent on May 24, 2007, claiming priority over the Benelli patent filed a year earlier. On November 29, 2011, it was awarded to Remington. If you are interested, it is US 8,065,949 B1.