Sig Sauer MCX Rattler (300 Blackout) with Telescoping Pistol Stabilizing Brace - Black

Out of stock - Join the waitlist to be emailed when this product becomes available


Rapid deployment, thin, agile and precise. This is the SIG MCX® Rattler. Featuring a 5.5″ PDW barrel, the MCX platform has never been more compact or accessible. Ready to go wherever it’s needed, the MCX Rattler PSB features a 3-position telescoping pistol brace for stability and easy concealment. This gun was designed from the ground up to be as discrete as possible while retaining all the robust capabilities of the MCX. Free-floating M-LOK® handguards matched with a PDW upper and 5.5″ barrel, the MCX Rattler PSB is the ideal choice for fast-moving operators.


Additional Information
ManufacturerSig Sauer
ModelMCX Rattler
TypePistol:  Semi-Auto
Caliber300 BLACKOUT
ActionGas Operated Semi-Auto
Receiver FinishHard Coat Anodized (Black)
SightsNo Sights
Barrel Length5.5″
Overall Length19.3″
Weight5.1 lbs
Pistol BraceSig Sauer Collapsible Stabilizing Brace
MagazineOne 30-Round Aluminum Magazine
UPC Product Code798681581306
Manufacturer SKUPMCX-300B-5B-TAP-PSB

Additional Information Content

Modern Warriors

We started Modern Warriors for the sole purpose of providing a less expensive way to enjoy our love of buying and shooting some really cool stuff. What started as a hobby has turned into a business where we have developed the experience and ability to help you enjoy our same hobby and save you money in the process.

We specialize in tactical weapons, including suppressors, short barrel rifles and full auto weapons. We have routine experience in shooting the weapons we carry, so if you want our opinion on how a weapon operates, we will gladly provide it. We also have expertise working with licensed professionals in setting up gun trusts, which is an ideal way of purchasing, owning and operating any weapon restricted by the National Firearm Act. Don’t let the word “trust” scare you. It is very easy to set one up if you have the right help.

Learn More

Due to COVID-19, our shipping department is not able to operate at full capacity which is causing a delay in order processing. In addition, all orders are shipped via UPS or FedEx who are also experiencing delivery delays. At the same time, we have experienced a significant increase in online orders. Our employees are working exceptionally hard every day to work towards getting back on track with orders, responding to customer inquiries, return requests all with the goal of getting caught up on our orders. As a result, please allow up to 7 days from the date of your order before your order is fulfilled. We apologize for this inconvenience.