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Sig Sauer M400-SDI XSERIES 5.56 16″ Rifle



  • Ambidextrous Bolt Catch and Release
  • Hybrid Compensating Flash Hider
  • Dual Clamp Handguard Locking System for Reduced Deflection
  • Low Profile Gas Block with Mid-Length System
  • SIG Flatblade Match Trigger
  • Magpul SL Stock

Availability: 1 in stock

SKU: RM400-SDI-16B-P Categories: , , Tag:

The M400-SDI XSERIES has been 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-SDI XSERIES to meet the highest standards of performance and reliability.

With fully ambidextrous controls including a bolt catch/and release unique to the M400-SDI lower-receiver, the M400-SDI XSERIES delivers advanced performance for both left & right-handed shooters and makes transitional shooting easier than ever.

The free-floating handguard utilizes a new steel lockup design that significantly reduces handguard deflection by providing maximum rigidity and allows for accessories to be attached on all four sides with no effect on accuracy.  The 2-Stage Matchlite Duo trigger provides an out-of-the-box crisp 4.5 – 6.5lb pull weight with a flat blade design for a precision feel.

The M400-SDI XSERIES utilizes the highest quality performance coatings to ensure maximum durability and reliability.


  • SKU: RM400-SDI-16B-P
  • Caliber: 5.56 NATO
  • Barrel Length: 16 inches
  • Mags Included: (1) 30 Round Polymer Magazine
  • Mag Type: AR-15
  • Action Type: Semi-Auto
  • Stock Type: 6-Position Magpul SL
  • Barrel Material: Chrome/Moly Steel
  • Trigger Type: SIG Flat Blade Match
  • Trigger Shape: Flat
  • Twist Rate: 1:7
  • Forend Type: Alloy
  • Grip Type: Polymer
  • Receiver Finish: Anodized
  • Overall Length: 33.5 inches (851 mm)
  • Overall width: 2.8 inches (6.98 mm)
  • Height: 7.5 inches ( 191 mm)
  • Threads 1-2 inches- 28 tpi
  • Accessory Rail: M-LOK
  • Forward Assist: Yes
  • Operating System: Direct Impingent
  • Weight; 7.0 Pounds (3.18 kg)
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M400-SDI XSERIESSig Sauer M400-SDI XSERIES 5.56 16″ Rifle

Availability: 1 in stock

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