US chose 5.56mm SIG Rattler 300BLK short rifle with AR-15 mag type

WASHINGTON — On May 19, the United States Special Operations Command [US SOCOM] announced its intention to purchase the Sig MCX Rattler 300 Blackout and NATO 5.56×45 mm short rifles as personal defense weapons under a five-year contract with one supplier.

US Special Forces get 5.56mm SIG MCX 300BLK with AR-15 mag type
Photo: Spotter UP

Sig Sauer MCX Rattler will be delivered complete with silencer, cleaning kits, shops, and quick-change barrel kits. The 5.56 mm version uses ammunition compatible with the larger M4A1 carbine and other standard American infantry rifles.

Both MCX Rattler calibers have a 14 cm barrel and receiver mounted on the lower AR15 receiver. The total length of the rifle is 60 centimeters, taking into account the elongated aluminum folding butt. The 300 Blackout version is 1.3 cm longer than the 5.56 mm rifle. Both models weigh about 2.7 kg without ammunition.

The rifles are equipped with a patented Sig M-LOK free-floating handle, which is its own accessory mounting system, equipped with a Picatinny accessory rail, with a double-sided reloading handle. SOCOM will also purchase SL Sig silencers for both rifle versions.

SOCOM was looking for a rifle with a 300 Blackout cartridge [7.62×35 mm metric], developed by the Advanced Armament Corporation [AAC] in collaboration with Remington in 2009 and offered mainly in two variants, 300 Whisper, and 300 AAC Blackout.

US Special Forces get 5.56mm SIG MCX 300BLK with AR-15 mag type
Photo: The NI

The 300 AAC Blackout instantly gained popularity. It has excellent ballistics, and accuracy and does not lose its characteristics even when using devices for silent shooting. The recoil of the weapon when using this ammunition is very soft and allows you to work with high accuracy even in fully automatic mode.

The dimensions of the cartridge [total length and diameter of the bottom] made it possible to use it in a re-barrel weapon, originally designed for .223 Remington / 5.56×45 mm cartridges.


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