This mini rifle could replace the pistol that Delta Force and Seal Team 6 have used for decades

Sig Sauer

The company that won the controversial competition to build the next U.S. military sidearm is throwing its hat into the ring to provide a potential replacement weapon for a weapon used by the nation's most elite counterterrorism units since the 1970s.

In March, U.S. Special Operations Command issued an advisory to industry. with a new “personal defense weapon” which had specifications that were almost impossible to achieve.

The weapon had to be no more than 26 inches with the stock extended, had to collapse to less than 17 inches AND be able to fire from the collapsed configuration.

And oh, the gun had to be designed to fire both .300 Blackout rounds and 5.56 rounds.

These rifles would replace the MP5 variants in special operations stockpiles – 9mm submachine guns that are both aging and provide significantly less effective range than more modern calibers compatible with sub-barrel length barrels.

Well, Sig Sauer, maker of the Army's new M17 and M18 handguns, has adopted the MP5 replacement plate with its new MCX “Rattler.”

“Groups came to see us and explained the situations to us [they] were being used with 9mm secondary pistols, the caliber is not appropriate,” Sig Sauer officials said during a live event returning the Rattler to the public.

They wanted “a backup gun with the firepower that [they] need.”

Sig Sauer/YouTube

Based roughly on Sig's MCX design, the Rattler has a 5.5-inch barrel and with its collapsible stock collapsed, the entire weapon measures just 16 inches long.

And he can shoot in this configuration.

“The PDW stock allows you to operate the weapon when folded,” Sig officials told RECOIL magazine. “It is the shortest rifle currently available on the market.”

In fact, the Rattler is only 3.5 inches longer than the ultimate CQB weapon – the MP5K.

“We wanted to give these guys a weapon that was the size of a secondary weapon, but had the firepower to shoot over 200 yards and effectively do what they needed to do,” Sig said.

The Rattler can fire suppressed in the 300 BLK configuration, but Sig says the barrel is too short to run 5.56 rounds with a can.

The Rattler's upper is swappable with any standard M4 or AR-15 style lower, checking the box on the SOCOM PDW request so the pistol can change calibers in less than three minutes.

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