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Sig Sauerar-15Value Tier

Sig Sauer M400 Forge

$999 duty-ready AR with factory TriggerTech trigger, Breek Warhammer charging handle, and Romeo MSR Gen II red dot included

Price
$999
Weight
6 lb 13 oz
Calibers
5.56x45mm
Rail
mlok

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KYGUNCO

SIG SAUER SIGM400 Forge 5.56 16" 30rd w/ Romeo-MSR Gen II - Black & Moss Green

$1099.99
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3d ago
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Overview

The Sig Sauer M400 Forge is Sig's 2026 answer to the duty-ready AR-15 segment, ships at $999 MSRP with a factory TriggerTech two-stage duty trigger, Breek Arms Warhammer ambidextrous charging handle, Magpul SL-K stock, 15-inch free-float M-LOK handguard, and a Romeo MSR Gen II red dot sight included. The barrel is cold hammer forged on the same machinery that produces Sig's premium MCX platform, with a full FMC coating throughout the bore and exterior. An H&K-style extractor support pin in the barrel extension is a safety feature rarely found at this price tier.

The Forge replaces the upgrade cycle most buyers perform on value-tier ARs. A standalone TriggerTech duty trigger retails for $150-250, the Breek Warhammer charging handle runs $80-90, the Romeo MSR Gen II optic carries an approximate $150 standalone value, and a hammer-forged barrel is typically a $200-300 upgrade on competing platforms. Combined with ambidextrous safety and magazine release controls (bolt release is left-side only), the factory bundle costs $400-500 less than building the equivalent spec from a value-tier host plus aftermarket parts. GunsAmerica's early testing reported zero malfunctions across several hundred rounds, with True Pearce noting the rifle "does not shoot like a $999 rifle."

Available in four finishes: black anodized (base price), Flat Dark Earth Cerakote, Concrete Gray Cerakote, and Moss Green Cerakote. Cerakote variants carry a modest premium over the $999 base. The mid-length gas system on the 16-inch barrel reduces port pressure and bolt velocity for smoother cycling and longer component life compared to carbine-length alternatives at the same price point. All configurations ship with one 30-round Magpul PMAG and are covered under Sig's Infinite Guarantee, a fully transferable lifetime warranty requiring no registration.

Key Features

  • 16" cold hammer forged barrel with full FMC coating (MCX tooling)
  • Mid-length direct impingement gas system
  • 1:7 twist rate for heavier projectiles
  • Factory TriggerTech duty trigger - two-stage flat blade, 3.5 lb
  • Breek Arms Warhammer ambidextrous charging handle
  • Sig Romeo MSR Gen II red dot included (2 MOA, 35,000-hr runtime, IPX7)
  • 15-inch free-float M-LOK aluminum handguard
  • Magpul SL-K 6-position stock
  • Ambidextrous safety selector and magazine release
  • H&K-style extractor support pin
  • A2 birdcage flash hider (1/2x28)
  • Available in black, FDE, Concrete Gray, and Moss Green Cerakote
  • Sig Infinite Guarantee (lifetime, transferable)

Capability Profile

0-10 Scale Across 8 Axes

Pros

  • +Factory TriggerTech two-stage duty trigger eliminates the most common AR-15 upgrade
  • +Cold hammer forged barrel produced on MCX machinery
  • +Romeo MSR Gen II red dot included at no added cost
  • +Breek Arms Warhammer charging handle - premium ambi upgrade from the factory
  • +H&K-style extractor support pin (rare at this price)
  • +Full 15-inch free-float M-LOK handguard with Picatinny top rail
  • +Ambidextrous safety and magazine release
  • +Sig Infinite Guarantee covers rifle AND included optic

Cons

  • −Left-side-only bolt release (single ergonomic limitation)
  • −Cerakote finishes cost more than the $999 black base
  • −Basic A2 birdcage muzzle device at this price
  • −No QD sling points molded into the handguard

Detailed Specifications

caliber
5.56 NATO
Barrel Length
16 inches
Overall Length
32.25" collapsed / 35.5" extended
weight
6.8 lbs
Gas System
mid-length
Twist Rate
1:7
barrel
Cold hammer forged, FMC coated
handguard
15-inch free-float M-LOK alloy
trigger
TriggerTech duty, two-stage flat, 3.5 lb
stock
Magpul SL-K 6-position
msrp
$999 (black); Cerakote variants higher

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Compatibility Tags

family: modern-riflefamily: ar-patterntrigger: ar-fcginterface: picatinny-tophandguard: mlokbarrel: longthread: 1/2x28mag-type: stanagreceiver-pattern: ar-15

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