New For 2024: SIG Sauer MCX Regulator

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posted on March 20, 2024
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SIG MCX Regulator 01
Images courtesy of SIG Sauer.

Some Americans live in locales where it is impossible to own an AR-15-type rifle in its standard configuration with separate stock and pistol grip. Others want the functionality of a modern sporting rifle in a more streamlined and traditional-looking package. For 2024, SIG Sauer is satisfying both with its MCX Regulator, a rifle that the company says is “re-defining the ranch rifle.”

The MCX Regulator is based around the design of the MCX with its rotating bolt operated by a short-stroke gas piston. In fact, the proprietary lower is compatible with any MCX upper. The lower is made of aluminum alloy and, just like the latest versions of the MCX, features fully ambidextrous controls, including bilateral magazine release buttons, safety and bolt release and an AR-type rear charging handle. The trigger is SIG’s two-stage match unit. The lower receiver has a built-in ARCA rail between the triggerguard and magazine well for mounting the rifle to a tripod.

Right side of the SIG Sauer MCX Regulator.The MCX Regulator is based upon the design of SIG’s MCX series of rifles.

Where the Regulator differs from other MCX models is in its rear stock configuration. The MCX’s short-stroke piston design contains its recoil springs within the receiver, meaning there is no need for a receiver extension. This allows the MCX Regulator to use a traditional-type one-piece buttstock. SIG uses a Magpul SGA stock that is compatible with Mossberg 500/590 models, a modular design that allows the user to customize length-of-pull and comb height. The Regulator’s profile makes it ideal for riding in a saddle scabbard or carried in a pickup truck.

Left side of the SIG Sauer MCX Regulator.The MCX Regulator’s buttstock is compatible with stock designed for the Mossberg 500/590 series.

The rifle is available chambered for two cartridges: 5.56 NATO or 7.62x39 mm. Both chamberings use a 16" cold hammer-forged barrel with their muzzles threaded and ship with a SIG-designed compensating muzzle brake in place. No sights are supplied, but the rifles are optics ready with a full-length Picatinny rail on the upper receiver and handguard. The aluminum handguard also has MLok slots. Major metal components are finished in a Gen II NiR FDE Cerakote for reduced IR signature. Magazines are AR-compatible and a 10-round version is supplied with each. Both versions have an overall length of right at 39" and weigh just at 8 lbs.

SIG Sauer MCX Regulator in a scabbard on the side of a horse, with tall grass in the foreground.The traditional profile of the MCX Regulator is right at home in a saddle scabbard.

The SIG MCX Regulator has an MSRP of $2,999 for either chambering or $3,499 for a 5.56 NATO model that comes from the factory with a SIG Romeo2 electronic optic installed. For more information, visit sigsauer.com.

Man aiming SIG Sauer MCX Regulator while using a wooden fence post as a front rest.The MCX Regulator is available with a factory-installed SIG Romeo2 red-dot optic.

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