The Winchester SX4 is a gas operated semi automatic shotgun built on Winchester's Active Valve gas system, which uses a piston assembly that self regulates gas pressure to cycle reliably across a range of loads from light field shells through heavy magnum rounds without manual adjustment. The Active Valve system vents excess gas as pressure increases, reducing felt recoil with heavier loads while maintaining sufficient energy to cycle lighter ones. The SX4 platform features a rotating bolt head that locks into the barrel extension, a chrome plated chamber and bore, and a drop out trigger group for simplified maintenance.

This example is the Upland field variant, distinguished by satin nickel finished aluminum alloy receiver with pheasant game scene and floral scroll engravings. It is chambered in 12 gauge with a 3 inch chamber and is fitted with a 28 inch barrel with a ventilated rib and fiber optic front sight. The barrel is threaded for Winchester Invector Plus choke tubes, with a Modified choke tube installed. The shotgun is configured with a satin finished walnut stock and forend with a 14.5 inch length of pull, adjustable with use of spacers. Accompanied by two additional Invector Plus choke tubes (Full and Improved Cylinder), extra buttpad spacers, and owner's manual.

Specifications

• Manufacturer: Winchester
• Model: SX4 Upland Field
• Gauge: 12 Gauge
• Chamber: 3 inch
• Action: Semi automatic, gas operated (Active Valve system)
• Barrel: 28 inches, chrome plated bore, ventilated rib
• Receiver: Aluminum alloy, satin nickel finish, game scene engraving
• Stock/Forend: Walnut, satin finish
• Length of Pull: 14.5 inches (adustable)
• Sights: Fiber optic front sight
• Choke System: Invector Plus (Modified installed; Full and Improved Cylinder included)
• Magazine: 4+1 tubular