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SIG SAUER M400 FORGE 5.56 RIFLE 16.5″ BBL, BLACK, ROMEO MSR G2, TELESTOCK 1-30RD MAG

SIG SAUER M400 FORGE 5.56 RIFLE 16.5″ BBL, BLACK, ROMEO MSR G2, TELESTOCK 1-30RD MAG

$999.99

16 in stock

Purchase & earn 1,000 points!

Disclaimer: It is the customer’s responsibility to ensure that all orders comply with applicable local and federal regulations. Non-compliant orders are subject to a 30% restocking fee. We reserve the right to dispute any chargebacks related to such orders.

Guidelines for Shipping Restrictions by State

Overview

The SIGM400 5.56 NATO rifle combines a 16 in barrel platform with a modern Romeo-MSR Gen II optic setup, a telescoping stock, and an AL M-LOK handguard to deliver a compact, ready-to-mount configuration for precision aiming and fast target acquisition.

Key Features

  • Caliber: 5.56 NATO
  • Action: Semi-automatic
  • Barrel length: 16 in
  • Finish/color: Black
  • Optics compatibility: Romeo-MSR Gen II
  • Stock: Telescoping
  • Handguard system: AL M-LOK HG
  • Magazine included: (1) 30 rd mag

Specifications

  • Product name: SIGM400
  • Firearm type: Rifle
  • Barrel profile/length designation: 16IN
  • Upper/forging designation: FORGE
  • Model designation: ROMEO-MSR GEN II
  • Accessory designation: TELE STOCK
  • Handguard designation: AL MLOK HG
  • Magazine capacity: 30 rounds

Benefits

  • Integrated optic-ready configuration: Supports a Romeo-MSR Gen II mounting arrangement for an established sighting system.
  • Compact 16 in form factor: Optimized proportions for maneuvering while maintaining a rifle-length barrel.
  • Telescoping stock: Provides adjustable length-of-pull for consistent shoulder fit.
  • M-LOK handguard interface: Enables mounting of compatible accessories along the handguard for organized setup.

Use Cases

  • Range sessions requiring a 5.56 NATO semi-automatic rifle with a 16 in barrel
  • Training that benefits from a telescoping stock and an optic-mounted layout
  • Target work using a 30 rd magazine for extended strings

Why Choose SIGM400

The SIGM400 is specified with a 16 in 5.56 NATO semi-automatic rifle build, a Romeo-MSR Gen II optic configuration, an adjustable telescoping stock, and an AL M-LOK handguard, packaged with a 30 rd magazine in a black finish for a cohesive, assembled configuration.

Your Trusted Online Firearms Store – Shop with Confidence!

Looking for the best prices on SIG SAUER M400 FORGE 5.56 RIFLE 16.5″ BBL, BLACK, ROMEO MSR G2, TELESTOCK 1-30RD MAG by Sig Sauer? ADA Armaments LLC proudly serves Boise with unbeatable pricing, expert service, and exclusive rewards.

Best Prices in Boise.
Earn Rewards on Every Purchase.
Special Bundles & Firearm Packages Available.
Safe & Secure Checkout – Shop with confidence using trusted payment options.
Compliance-Ready – All sales follow federal, state, and local firearm laws.

No shipping to California.

Limited Stock – Visit Us Today or Shop Online Before They’re Gone! 

UPC

798681744114

Manufacturer

Manufacturer Part Number

RM400556N16BFORGE

Action

Semi-Auto

Barrel Length

16"

Caliber/Gauge

.223 REM/5.56 NATO

Capacity

30

Model

M400 Forge

Product Type

AR

Rate of Twist

1:7"

Shipping Weight

9.4

SKU: ORI|73504Categories: AR Rifles

Overview

The SIGM400 5.56 NATO rifle combines a 16 in barrel platform with a modern Romeo-MSR Gen II optic setup, a telescoping stock, and an AL M-LOK handguard to deliver a compact, ready-to-mount configuration for precision aiming and fast target acquisition.

Key Features

  • Caliber: 5.56 NATO
  • Action: Semi-automatic
  • Barrel length: 16 in
  • Finish/color: Black
  • Optics compatibility: Romeo-MSR Gen II
  • Stock: Telescoping
  • Handguard system: AL M-LOK HG
  • Magazine included: (1) 30 rd mag

Specifications

  • Product name: SIGM400
  • Firearm type: Rifle
  • Barrel profile/length designation: 16IN
  • Upper/forging designation: FORGE
  • Model designation: ROMEO-MSR GEN II
  • Accessory designation: TELE STOCK
  • Handguard designation: AL MLOK HG
  • Magazine capacity: 30 rounds

Benefits

  • Integrated optic-ready configuration: Supports a Romeo-MSR Gen II mounting arrangement for an established sighting system.
  • Compact 16 in form factor: Optimized proportions for maneuvering while maintaining a rifle-length barrel.
  • Telescoping stock: Provides adjustable length-of-pull for consistent shoulder fit.
  • M-LOK handguard interface: Enables mounting of compatible accessories along the handguard for organized setup.

Use Cases

  • Range sessions requiring a 5.56 NATO semi-automatic rifle with a 16 in barrel
  • Training that benefits from a telescoping stock and an optic-mounted layout
  • Target work using a 30 rd magazine for extended strings

Why Choose SIGM400

The SIGM400 is specified with a 16 in 5.56 NATO semi-automatic rifle build, a Romeo-MSR Gen II optic configuration, an adjustable telescoping stock, and an AL M-LOK handguard, packaged with a 30 rd magazine in a black finish for a cohesive, assembled configuration.

Your Trusted Online Firearms Store – Shop with Confidence!

Looking for the best prices on SIG SAUER M400 FORGE 5.56 RIFLE 16.5″ BBL, BLACK, ROMEO MSR G2, TELESTOCK 1-30RD MAG by Sig Sauer? ADA Armaments LLC proudly serves Boise with unbeatable pricing, expert service, and exclusive rewards.

Best Prices in Boise.
Earn Rewards on Every Purchase.
Special Bundles & Firearm Packages Available.
Safe & Secure Checkout – Shop with confidence using trusted payment options.
Compliance-Ready – All sales follow federal, state, and local firearm laws.

No shipping to California.

Limited Stock – Visit Us Today or Shop Online Before They’re Gone! 

UPC

798681744114

Manufacturer

Manufacturer Part Number

RM400556N16BFORGE

Action

Semi-Auto

Barrel Length

16"

Caliber/Gauge

.223 REM/5.56 NATO

Capacity

30

Model

M400 Forge

Product Type

AR

Rate of Twist

1:7"

Shipping Weight

9.4

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