SIG M400 UPPER RECEIVER ASSEMBLY - 11.5" 5.56 NATO

Take your M4/AR15 to the next level with this complete M400 upper assembly.

 

NO RECEIPTS

NO WARRANTY CARDS

FULLY-TRANSFERABLE

FOREVER

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Availability:

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Price $1,199.99
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Features

COMPLETE 11.5-INCH M400 5.56 NATO UPPER ASSEMBLY.

EASILY INSTALLATION.

INCLUDED ROMEO5 GEN II RED DOT.

Details

Upgrade your M4/AR rifle or lower assembly with this complete, drop-in M400 upper assembly. This kit includes all the necessary components for a complete swap, including a ROMEO5 GEN II Red Dot. The free-floating handguard utilizes a new steel lockup design that significantly reduces handguard deflection by providing maximum rigidity and allowing for accessories to be attached on all four sides with no effect on accuracy. Together, this kit gives you the one-stop solution when it comes to taking your M4/AR to the next level.

The M400 was developed with the input from the professional instructors at SIG SAUER Academy. Building upon their decades of experience and countless hours of instruction, we have developed the M400 to meet the highest standards of performance and reliability.

INCLUDED ITEMS:

  • (1) Complete 11.5" 5.56 NATO Upper Assembly
  • (1) ROMEO5 GEN II 1x20MM Red Dot

11.5" 5.56NATO M400 UPPER ASSEMBLY FEATURES INCLUDE:

  • Black Anodized Finish
  • Dual Clamp Handguard Locking System for Reduced Deflection
  • Low-Profile Gas Block with Mid-Length Gas System
  • High-quality, premium barrel

ROMEO5 GEN II 1x20MM FEATURES:

  • Ruggedized Industrial Design
  • I-BEAM Mount for maximizing situational awareness
  • 12 Settings (10 Day + 2 NV)
  • 40,000 hrs Runtime with CR2032 Battery and MOTAC™ Motion Activated
  • Top Mount Illumination Controls for Ambidextrous Operation
  • Dependable IPX7 Waterproof and Fog-Proof Performance
  • Parallax-Free Optical Design

Specifications

SKU UAM400-556N-11B-SDI-BLK-R5G2
Model SIGM400
Barrel Extension M400
Barrel Length 11.5 in [292.1 mm]
Bolt Carrier Finish FNC
Bolt Carrier Group Included Yes
Caliber 5.56 NATO
Chrome Lined Barrel No
Charging Handle Included Yes
Color Black
Forward Assist Yes
Free Floated Handguard Yes
Gas System Length Mid Length
Handguard Inside Diameter 1.25-in
Handguard Material Aluminum
Muzzle Device SIG Flash Hider-Compensator
Muzzle Thread Pitch 1/2-28
Operating System Gas
Receiver Finish Black Anodized
Twist Rate 1:7
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