The SIG556 Patrol takes advantage of a shorter gas piston to reduce weight and employ a shorter forend — making it ideal for patrol officers. Shown here with Aimpoint dot sight.

The 5.56x45mm SIG556 rifle from Sig Sauer has has always struck me as a valid alternative to the AR-15/M16 platform since its introduction in the U.S. While the SIG 556 product line accepts AR-15/M16 magazine (a major plus to my way of thinking), it is closer to the Kalashnikov in actual operating method in that it utilizes a gas-piston operating rod system with a rotating bolt and carrier very similar to the AK’s in configuration. The Sig operating rod system is often referred to as the Porsche of AK designs, due to the tighter tolerances and better workmanship found in Sig Sauer weapons as compared to other manufacturers using the AK as a basis of design. The adjustable gas-piston operating system keeps the action cleaner, cooler, and overall more reliable. It also allows the use of side-folding stocks to reduce overall dimensions of the rifle when needed.

These are all positive attributes, especially considering the recent rush to create gas-piston ARs due to the increased reliability factor. Many in the U.S. market waited on Sig Sauer’s entry into the “black” rifle market with the hope of getting a civilian version of the legendary Swiss Army Sig 550 series of rifles. Sig Sauer designers chose a compromise, as the SIG556 trigger housing was altered from the 550-series
to accept AR-15 magazines. However, the proven two-position adjustable gas-piston operating rod system found on the 550 series was maintained in the 556’s design.

Gun Details

The SIG556 Patrol uses an adjustable two-position gas regulator along with distinctive forearm furniture. The sling attachment point offers the flexibility of using a two-point sling.

Any department or individual officer looking for an LE patrol carbine would instantly appreciate the Sig Sauer 556 Patrol Rifle. The functionality of a rifle utilizing AR-15 magazines while incorporating a proven gas-piston operating rod system with a heritage that’s tied to the legendary Sig 550 is certainly hard to deny. Not to mention the fact that this quick-handling, ergonomic rifle design can be easily transported (especially with the stock folded). The Sig Sauer 556 Patrol Rifle integrates excellent accuracy from the 16-inch barrel with efficient handling and maneuverability. Thus, no matter the situation an officer may find him/herself in—whether it is a rural setting with longer distances encountered one or more urban requiring CQB-style tactics—the Sig Sauer 556 Patrol can satisfy the mission.

The SIG556 Patrol has a “flattop” upper receiver with a Picatinny rail for mounting optics or other aiming devices. One unique feature of the SIG556 product line is the Rotary Diopter Sight System (RDSS). The Sig RDSS with a rotary drum rear sight and front post is more substantial than most iron sight configurations. A shooter is well served by the RDSS if an optic device is not utilized or goes down. The RDSS stems from the 556’s Sig 550 heritage and is befitting a service rifle that relies solely on its open sights to engage targets. However, recent trends in fighting rifles would indicate the design intent for the SIG556 Patrol is to mount some sort of low-powered magnified optic or red dot as the primary sighting tool.