SIG Sauer MCX Rattler 300 Blackout SBR - 5.5"

Manufactured by Sig Sauer
Manufactured by Sig Sauer
1 Review

Out of Stock

Items that are regulated by the ATF and NFA have restrictions and requirements: •Your Entire Order will ship only to a Federal Firearm License holder •NFA restricted items require class 3 licensing and documentation •A copy of your order/invoice as well as the current FFL License for your local dealer must be emailed to ffl@primaryarm



Note: This is an NFA regulated short barreled rifle (SBR). Know your jurisdiction's NFA laws before ordering this rifle.

The MCX Rattler is the by product of a request from US Special Operations who needed a PDW or personal defense weapon to replace the MP5. Sig Sauer stepped up to the plate big time with Rattler. This rifle, uh we mean pistol, no, really it’s a rifle is truly groundbreaking innovation wrapped up in a 16” total length when the stock is folded.

Sig Sauer already had a reputation for modular weaponry with their flagship MCX rifle which featured a short-stroke recoil gas piston operating system, so the Rattler came with fantastic technological “bloodlines”.

  • Barrel Length: 5.5”
  • Trigger: Sig Enhanced
  • Caliber: .300 BLK
  • Picatinny Rail: M1913 M-LOC
  • Action: Semi-Auto
  • Suppressed or unsuppressed fire: Two position gas regulator
  • Finish/Color: Black 
  • Stock: Folding 

What makes Sig Sauer’s platform so radically different from other AR/M4 style rifles is the recoil system completely eliminates the need for a buffer tube which means the rifle can be manufactured to be much more compact than any other rifle of its style.

The MCX Rattler short barrel rifle has an astoundingly small “wingspan” of only 16” when the stock is folded and both the PSB (pistol version) ad the SBR version weigh under 6 pounds. The MCX Rattler SBR comes chambered in .300 BLK and sports a tiny 5.5” barrel and the barrel is suppressor ready for an effective whisper quiet shot.

Rounding out the tactical perfection of the MCX Rattler is a M1913 M-LOK rail which runs from the charging handle all the way to the muzzle, and the Rattler comes with Sig Sauer Sig Enhance Trigger system for ease of continued firing.
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Barrel Coating
Barrel Length5.5
BrandSig Sauer
Caliber Gauge300 Blackout
Gas System TypeShort Stroke Gas Piston
Muzzle Device3-Prong Flash Hider
Thread Pattern5/8 X 24
Twist Rate1:5

Ratings & Reviews

1 review

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accurate gun


i owned this gun last month and it is very good for home defense , very good