Sig Sauer MCX Rattler .300 Blackout 5.5" Upper AR Conversion

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Your Price: $1,449.99
Retail Price:$1,799.00
You Save:$349.01(19%)
Sig Sauer MCX Rattler .300 Blackout complete upper receiver with AR conversion kit. This Sig MCX Rattler upper has a 5.5" PDW barrel and a free floating M-LOK handguard to make it the most compact, agile upper receiver available. This kit comes with the complete MCX upper receiver, adapters to convert a standard Mil-Spec AR15 lower receiver so it's functional with the upper, and Sig's Match Duo 2 stage trigger, everything needs to remove your current AR rifle upper and upgrade to the MCX easily.
Part Number: SMCXRC-BLK
Availability: In Stock.
Sig Sauer MCX Rattler .300 Blackout complete upper receiver with AR conversion kit.  This Sig MCX Rattler upper has a 5.5" PDW barrel and a free floating M-LOK handguard to make it the most compact, agile upper receiver available.  This kit comes with the complete MCX upper receiver, adapters to convert a standard Mil-Spec AR15 lower receiver so it's functional with the upper, and Sig's Match Duo 2 stage trigger, everything needs to remove your current AR rifle upper and upgrade to the MCX easily.

Sig MCX Rattler 5.5" Complete AR Conversion Kit in .300 Blackout Features:



  • Made with Sig's highest standards and specifications
  • Comes assembled and ready to install
  • Has two position gas valve so it can be used suppressed or unsuppressed
  • This complete kit includes the following items:
    • Sig MCX Rattler upper with M-LOK handguards
    • Charging Handle
    • Bolt Carrier Group
    • Sig Duo Matchlite Trigger
    • 1913 Adapter to convert standard AR lower to accept the MCX upper
  • Finished in Black
  • Have the ability to build your AR pistol with a folding brace and still maintain the functionality