Sig Sauer MCX Rattler (300 Blackout) w/Pistol Stabilizing Brace and Holosun HS510C Open Reflex Sight

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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.

Holosun offers an open reflex sight product family which provides a larger field of view than our micro dots as well as the following advantages:

  • Advanced LED Technology: Holosun has developed high efficiency LED technology that draws current at the micro-ampere level, extending the average CR2032 battery life up to 50,000 hours. At the same time, Holosun also has the capability to customize the shape of the LED to create different reticle options. For example, our 500 series red dot’s reticle is a 65 MOA ring around a 2 MOA dot, but the user has the option to turn off the ring and use just the dot if the need arises.
  • Unique Solar Technology: In our solar powered “C” series red dots, the brightness of recticle is automatically adjusted based on the ambient light hitting the solar panel. Thus, the solar panel is both a power supply and a light sensor. The backup battery will compensate if the optic cannot be powered by light alone.
  • Advanced Glass & Coatings: Holosun has created a proprietary multi-layer coating on the objective lens to ensure full spectrum light transmittance and clarity. Holosun also carefully pairs the front and rear glass to eliminate parallax.
  • Smart Features: Functions such as motion based on and off, memory of the last brightness & reticle style, and automatically adjusting reticle intensity are available on some models.


Additional Information
ManufacturerSig Sauer
ModelMCX Rattler w/ Pistol Stabilizing Brace
TypePistol:  Semi-Auto
Caliber300 BLACKOUT
ActionGas Operated Semi-Auto
OpticHolosun HS510C Open Reflex Sight
Barrel Length5.5″
Overall Length19.3″
Weight5.1 lbs
Pistol BraceSig Sauer Collapsible Stabilizing Brace
MagazineOne 30-Round Aluminum Magazine, Holosun Optic
UPC Product Code798681581306
Manufacturer SKUPMCX-300B-5B-TAP-PSB

Additional Information Content

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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.

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