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

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

$1,099.99

30 in stock

Purchase & earn 1,100 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

Product Overview

The SIGM400 5.56 NATO RIFLE is a 16-inch semi-automatic AR-platform configuration featuring a Romeo-MSR Gen II optic, a telescoping stock, an aluminum M-LOK handguard, and an FDE finish. The package includes one 30-round magazine.

Key Features

  • Caliber: 5.56 NATO
  • Action: Semi-automatic
  • Barrel length: 16 in
  • Handguard: Aluminum M-LOK HG
  • Stock: Telescoping (tele stock)
  • Optic: Romeo-MSR Gen II
  • Finish: FDE
  • Included magazine: (1) 30RD MAG

Specifications

  • Model: SIGM400
  • Firearm type: Rifle
  • Cartridge: 5.56 NATO
  • Operating mode: Semi (semi-automatic)
  • Barrel length: 16 in
  • Handguard system: AL M-LOK
  • Optics system: ROMEO-MSR GEN II
  • Stock configuration: Tele stock
  • Color/finish: FDE
  • Magazine capacity: 30 rounds

Benefits

  • Integrated optic platform: Romeo-MSR Gen II supports rapid target acquisition with a red-dot style sighting system.
  • M-LOK handguard: Aluminum M-LOK HG provides accessory mounting interfaces for configurable setups.
  • Telescoping stock: Adjustable length of pull supports consistent cheek weld and sight alignment across varying positions.
  • 16-inch configuration: Balances compact handling with a standard rifle-length sighting geometry.

Use Cases

  • Range sessions requiring a ready-to-mount optic configuration
  • Training drills benefiting from adjustable stock geometry
  • Configurations using M-LOK accessory mounting on a 16-inch rifle build

Why Choose This SIGM400 Build

This SIGM400 configuration pairs a 16-inch 5.56 NATO semi-automatic rifle with a Romeo-MSR Gen II optic, an aluminum M-LOK handguard, and a telescoping stock, delivered with a 30-round magazine and finished in FDE.

Your Trusted Online Firearms Store – Shop with Confidence!

Looking for the best prices on SIG SAUER M400 FORGE 5.56 RIFLE 16.5″ BBL, FDE, 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

798681744190

Manufacturer

Manufacturer Part Number

RM40055616FORGFDE

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

9.8

SKU: ORI|73506Categories: AR Rifles

Product Overview

The SIGM400 5.56 NATO RIFLE is a 16-inch semi-automatic AR-platform configuration featuring a Romeo-MSR Gen II optic, a telescoping stock, an aluminum M-LOK handguard, and an FDE finish. The package includes one 30-round magazine.

Key Features

  • Caliber: 5.56 NATO
  • Action: Semi-automatic
  • Barrel length: 16 in
  • Handguard: Aluminum M-LOK HG
  • Stock: Telescoping (tele stock)
  • Optic: Romeo-MSR Gen II
  • Finish: FDE
  • Included magazine: (1) 30RD MAG

Specifications

  • Model: SIGM400
  • Firearm type: Rifle
  • Cartridge: 5.56 NATO
  • Operating mode: Semi (semi-automatic)
  • Barrel length: 16 in
  • Handguard system: AL M-LOK
  • Optics system: ROMEO-MSR GEN II
  • Stock configuration: Tele stock
  • Color/finish: FDE
  • Magazine capacity: 30 rounds

Benefits

  • Integrated optic platform: Romeo-MSR Gen II supports rapid target acquisition with a red-dot style sighting system.
  • M-LOK handguard: Aluminum M-LOK HG provides accessory mounting interfaces for configurable setups.
  • Telescoping stock: Adjustable length of pull supports consistent cheek weld and sight alignment across varying positions.
  • 16-inch configuration: Balances compact handling with a standard rifle-length sighting geometry.

Use Cases

  • Range sessions requiring a ready-to-mount optic configuration
  • Training drills benefiting from adjustable stock geometry
  • Configurations using M-LOK accessory mounting on a 16-inch rifle build

Why Choose This SIGM400 Build

This SIGM400 configuration pairs a 16-inch 5.56 NATO semi-automatic rifle with a Romeo-MSR Gen II optic, an aluminum M-LOK handguard, and a telescoping stock, delivered with a 30-round magazine and finished in FDE.

Your Trusted Online Firearms Store – Shop with Confidence!

Looking for the best prices on SIG SAUER M400 FORGE 5.56 RIFLE 16.5″ BBL, FDE, 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

798681744190

Manufacturer

Manufacturer Part Number

RM40055616FORGFDE

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

9.8

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