Sig Sauer RM400556N16BFORGE10 M400 Forge 5.56 NATO 10+1 16" Black Anodized Alloy Receiver w/Picatinny Rail, M-LOK Handguard, Magpul SL-K Black Polymer Stock, Black Polymer Grip, Sig ROMEO MSR Gen II R

Note: This product must be shipped to an Federal Firearms Licensed Dealer(FFL Dealer)

Product Overview

The SIGM400 5.56 NATO rifle with a 16 in barrel delivers a semi-automatic platform built around a Romeo-MSR Gen II optic, a telescoping stock, and an aluminum M-LOK handguard in a black finish. The package includes a 10-round magazine.

Key Features

• Caliber: 5.56 NATO
• Action: Semi-automatic
• Barrel length: 16 in
• Optic: Romeo-MSR Gen II
• Stock: Telescoping stock (Tele Stock)
• Handguard: Aluminum M-LOK HG
• Finish: Black
• Magazine included: (1) 10RD MAG

Specifications

• Product name: SIGM400
• Cartridge: 5.56 NATO
• Fire control: Semi
• Barrel length: 16 in
• Optics model: Romeo-MSR Gen II
• Handguard system: M-LOK (aluminum)
• Magazine capacity: 10 rounds
• Color/finish: Black

Benefits and Performance Notes

With a 16 in barrel and integrated Romeo-MSR Gen II optic, the SIGM400 is configured for quick target acquisition and consistent sighting alignment. The telescoping stock supports adjustment for different shooting positions, while the aluminum M-LOK handguard provides a modular mounting interface for accessories.

Use Cases

• Range sessions with 5.56 NATO ammunition
• Training activities requiring a semi-automatic 16 in configuration
• Target-focused setups benefiting from an included red-dot optic
• Accessory-equipped builds using an M-LOK handguard