The Benelli M4 is a semi-automatic shotgun operating on Benelli's Auto Regulating Gas Operated (A.R.G.O.) system. Unlike conventional gas systems that route gases through a port into a cylinder surrounding the magazine tube, the A.R.G.O. system uses two small stainless steel self-cleaning pistons positioned just ahead of the chamber that act directly on the bolt carrier. This simplified gas path reduces the number of moving parts and eliminates the need for gas adjustment, allowing the M4 to cycle a wide range of 2 3/4 inch and 3 inch ammunition without modification. The rotating bolt locks into the barrel extension with dual lug engagement. The M4 is built on an anodized aluminum alloy receiver with the top of the receiver drilled and tapped for a Picatinny rail section for optics mounting. Sighting consists of a ghost ring aperture rear sight, adjustable for windage and elevation, and a fixed blade front sight. 

This example is configured with a fixed synthetic pistol grip stock and a 5-round magazine tube. The barrel measures 18.5 inches and is threaded for Benelli choke tubes, with a Modified choke currently installed. The receiver, barrel, and magazine tube feature a matte black anodized finish. No original box or accessories included.

Specifications

• Manufacturer: Benelli
• Model: M4 (11707)
• Gauge: 12 Gauge
• Chamber: 3 inch
• Action: Semi-automatic, gas operated (A.R.G.O.)
• Barrel: 18.5 inches, matte black finish
• Choke: Threaded for Benelli Crio chokes (Modified installed)
• Receiver: Aluminum alloy, anodized matte black, drilled and tapped Picatinny rail
• Stock: Fixed synthetic pistol grip
• Sights: Ghost ring rear (adjustable for windage and elevation), fixed blade front
• Magazine: 5+1, tubular magazine