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Armed Professional Program

SIG M400 PRO

Accurate, lightweight and crafted from the finest components, the SIGM400 PRO sets the new standard for direct-impingement AR-15s.

Specs

OPERATING SYSTEM
Direct Impingement
CALIBER
5.56 NATO
OVERALL LENGTH
36.5 in (972 mm)
OVERALL WIDTH
2.5 in (64 mm)
HEIGHT
7.5 in (191 mm)
BARREL LENGTH
16 in (406 mm)
WEIGHT
6.5 lb (2.95 kg)
TWIST RATE
1:7
MAG TYPE
AR-15

Details

Our competition fails to realize that a rock-solid foundation only gets you so far. That explains why many of today’s rifles ship with plastic handguards and throwaway furniture, two things not found on the SIGM400 PRO, SIG SAUER’s take on what an AR-15 should be. This carbine comes with the good stuff—all of it—pre-installed. Like a free-floating M-LOK handguard, which promotes accuracy and handling. Or a quality grip and premium, 6-position buttstock with integral QD points. The M400 PRO comes standard with AMBI controls. The Enhanced SIG Trigger on the M400 PRO enables the shooter to extract excellent accuracy from the rifle’s lightweight, 16” nitride barrel that is equipped with a SIG Micro-light Gas Block.

Models

Browse by individual sku to find the right product for you.

Buy Now SKU CALIBER BARREL LENGTH MAGS INCLUDED MAG TYPE SIGHTS ACTION TYPE STOCK TYPE BARREL MATERIAL TRIGGER TYPE COLLAPSED/FOLDED LENGTH TRIGGER WEIGHT TWIST RATE FOREND TYPE GRIP TYPE RECEIVER FINISH OVERALL LENGTH OVERALL WIDTH HEIGHT THREADS ACCESSORY RAIL OPERATING SYSTEM WEIGHT
N/A WRM400-16B-PRO 5.56 NATO 16" (406mm) (1) 30rd Aluminum Mag AR-15 SIG Flip Up Locking Semi-Auto Telescopic Cold Hammer Forged Carbon Steel Standard 1:7 Alloy Polymer Hard Coat Anodized 36.5" (972mm) 2.5" (64mm) 7.5" (191mm) 1/2 in - 28 tpi M-LOK Direct Impingement 6.5 lbs (2.95 kg)
N/A WRM400-16B-PRO-MGA 5.56 NATO 16" (406mm) (1) 30rd Aluminum Mag AR-15 SIG Flip Up Locking Select Fire Telescopic Cold Hammer Forged Carbon Steel Standard 1:7 Alloy Polymer Hard Coat Anodized 36.5" (972mm) 2.5" (64mm) 7.5" (191mm) 1/2 in - 28 tpi M-LOK Direct Impingement 6.5 lbs (2.95 kg)
N/A WRM400-16B-PRO-FDE 5.56 NATO 16" (406mm) (1) 30rd Aluminum Mag AR-15 SIG Flip Up Locking Semi-Auto Telescopic Cold Hammer Forged Carbon Steel Standard 1:7 Alloy Polymer Hard Coat Anodized 36.5" (972mm) 2.5" (64mm) 7.5" (191mm) 1/2 in - 28 tpi M-LOK Direct Impingement 6.5 lbs (2.95 kg)
N/A WRM400-16B-PRO-MGA-FDE 5.56 NATO 16" (406mm) (1) 30rd Aluminum Mag AR-15 SIG Flip Up Locking Select Fire Telescopic Cold Hammer Forged Carbon Steel Standard 1:7 Alloy Polymer Hard Coat Anodized 36.5" (972mm) 2.5" (64mm) 7.5" (191mm) 1/2 in - 28 tpi M-LOK Direct Impingement 6.5 lbs (2.95 kg)
N/A WRM400-16B-PRO-CB 5.56 NATO 16" (406mm) (1) 30rd Aluminum Mag AR-15 SIG Flip Up Locking Semi-Auto Telescopic Cold Hammer Forged Carbon Steel Standard 1:7 Alloy Polymer Hard Coat Anodized 36.5" (972mm) 2.5" (64mm) 7.5" (191mm) 1/2 in - 28 tpi M-LOK Direct Impingement 6.5 lbs (2.95 kg)
N/A WRM400-16B-PRO-CB-FDE 5.56 NATO 16" (406mm) (1) 30rd Aluminum Mag AR-15 SIG Flip Up Locking Semi-Auto Telescopic Cold Hammer Forged Carbon Steel Standard 1:7 Alloy Polymer Hard Coat Anodized 36.5" (972mm) 2.5" (64mm) 7.5" (191mm) 1/2 in - 28 tpi M-LOK Direct Impingement 6.5 lbs (2.95 kg)

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