M400-SDI X

Designed from the ground up to deliver maximum performance and reliability.

 

NO RECEIPTS

NO WARRANTY CARDS

FULLY-TRANSFERABLE

FOREVER

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Models

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RM400-SDI-16B-P
Rifle
5.56 NATO
Optics Ready
16 in [406.4 mm]
Chrome / Moly Steel
1:7
1/2 in - 28 tpi tapered shoulder
SIG Flash Hider-Compensator
Semi-Auto
Mid-Length Direct Impingement
6-Position Black Magpul SL
Reduced Angle
SIG 2-Stage Matchlite Duo
Flat
Ambidextrous
M-LOK Black Anodized Alloy
M-LOK/Picatinny
(1) 30rd Polymer Mag
Black
Hard Coat Anodized
36.5 in [927 mm]
33.3 in
N/A
2.8 in [71 mm]
7.1 in
7.0 lb [3.2 kg]
Yes
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RM400-SDI-16B-MSGRN
Rifle
5.56 NATO
Optics Ready
16 in [406.4 mm]
Chrome / Moly Steel
1:7
1/2 in - 28 tpi tapered shoulder
SIG Flash Hider-Compensator
Semi-Auto
Mid-Length Direct Impingement
6-Position Magpul MOE-SL, Black
Reduced Angle
SIG 2-Stage Matchlite Duo
Flat
Ambidextrous
M-LOK Moss Green Cerakote
M-LOK/Picatinny
AR-15
(1) 30rd Polymer Mag
Moss Green Cerakote
Moss Green Cerakote TM
36.5 in [927 mm]
33.25 in
N/A
2.8 in [71 mm]
7.1 in
7.0 lb [3.2 kg]
Yes
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RM400-SDI-16B-FDE
Rifle
5.56 NATO
Optics Ready
16 in [406.4 mm]
Chrome / Moly Steel
1:7
1/2 in - 28 tpi tapered shoulder
SIG Flash Hider-Compensator
Semi-Auto
Mid-Length Direct Impingement
Magpul BSL Pistol Stabilizing Brace
Reduced Angle
SIG 2-Stage Matchlite Duo
Flat
Ambidextrous
M-LOK FDE
M-LOK/Picatinny
AR-15
(1) 30rd Polymer Mag
Flat Dark Earth (FDE)
FDE Cerakote
36.5 in [927 mm]
33.25 in
N/A
2.75 in [70 mm]
7.1 in
7.0 lb [3.2 kg]
Yes
Gallery
Features
Details
Reviews
Features

Fully Ambidextrous Controls (bolt catch/release, safety selector, charging handle, mag catch)

Compensating Flash Hider for Reduced Muzzle Rise and Flash

SIG 2-Stage Matchlite Duo

Details

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

M400-SDI X FEATURES INCLUDE:

  • Available with a Moss Green Cerakote, FDE Cerakote or Black Anodized Finish
  • Ambidextrous Bolt Catch and Release
  • Compensator/Flash Hider
  • Dual Clamp Handguard Locking System for Reduced Deflection
  • Low-Profile Gas Block with Mid-Length Gas System
  • SIG 2-Stage Matchlite Duo Trigger
  • Magpul SL Stock
Resources
  • M400 SDI / DH3 RIFLE OWNER'S MANUAL
Reviews
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