SIG Sauer M400 5.56 NATO 16" 10+1 or 30+1 Monolithic rail system Carbine

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MSRP: $1,529.99
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Info

SKU:180054 ,UPC:

SKU: 180054

UPC: 798681725229

MPN: RM40016BROSER5X210

Info

SKU:
180054
UPC:
798681725229
MPN:
RM40016BROSER5X210

Specifications

ffl_type,

Specifications

ffl_type:
firearm

Description

The SIG Sauer M400 5.56 NATO 16" carbine with monolithic rail system delivers the reliability and modularity demanded by law enforcement, military professionals, and serious civilian shooters. Built on proven direct-impingement design, this platform has become the standard across tactical communities for its accuracy out of the box and ability to support mission-critical configurations. At 15.5 lbs fully configured, the M400 strikes the balance between pointability and durability that matters in high-stress environments where every ounce and every millisecond counts.

The monolithic rail system is the defining feature of this platform—a single-piece upper receiver and handguard that eliminates flex points and reduces zero shift when mounting optics, lights, or other accessories. This rigid structure improves shot-to-shot consistency and allows you to confidently shift between multiple optic configurations without re-zeroing. The 16-inch barrel offers optimal velocity for 5.56 NATO while maintaining the handling characteristics essential for close-quarters and vehicle-based operations. Magazine capacity options of 10+1 or 30+1 rounds accommodate both restricted jurisdictions and standard tactical loadouts, ensuring this carbine meets your local legal requirements without compromise.

Law enforcement agencies deploying this platform appreciate its rail real estate for mounting lights, laser devices, and offset optics—critical for low-light responses and dynamic entries. Military units benefit from its compatibility with standard NATO accessories and predictable ergonomics that reduce transition training time for mixed-team deployments. Civilian buyers selecting the M400 gain a duty-grade rifle with professional-level accuracy and a modular platform that grows with mission requirements. Whether you're preparing for professional service, serious sport shooting, or reliable home defense, the monolithic design ensures your accessory investment remains secure and your zero remains true through thousands of rounds.

SpecificationDetail
Brand
SIG SAUER
MPN / Part Number
RM40016BROSER5X210
UPC
798681725229
SKU
180054
Weight
15.5 lbs
Dimensions
14.9 x 4.3 x 44.2 in
Caliber
5.56 NATO
Barrel Length
16 inches
Magazine Capacity Options
10+1 or 30+1 Rounds
Rail System
Monolithic (Integrated Upper/Handguard)
Operating System
Direct Impingement
Accessory Compatibility
Picatinny Rails, Standard NATO Accessories

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