SIG SAUER M400 TREAD COIL Semi-Auto Rifle RM40016BTRDCOIL — Description

The SIG SAUER M400 TREAD COIL RM40016BTRDCOIL is a feature-enhanced .223 Remington / 5.56 NATO semi-automatic rifle built on SIG Sauer’s proven M400 platform. Designed as a complete modern sporting rifle, the TREAD COIL combines a lightweight aluminum receiver set, free-floating M-LOK handguard, adjustable stock, and upgraded SIG Matchlite trigger system for improved accuracy and handling.

The M400 TREAD COIL features a 16-inch barrel, direct gas impingement operating system, and a 6-position telescoping stock for adaptable fit and transport. The rifle’s free-floating M-LOK handguard provides mounting space for compatible accessories, while the flat-top receiver allows users to easily configure optics and sights.

Chambered in .223 Remington / 5.56 NATO, the rifle uses standard AR-15 pattern magazines and ships with a 30-round magazine. The TREAD COIL configuration upgrades the standard M400 TREAD package with SIG’s enhanced trigger system, making it a versatile option for range shooting, training, and general-purpose rifle applications.

SIG SAUER M400 TREAD COIL RM40016BTRDCOIL — Specifications

Manufacturer: SIG SAUER
Model: M400 TREAD COIL
Model Number: RM40016BTRDCOIL
Caliber: .223 Remington / 5.56 NATO
Action: Semi-automatic
Operating System: Direct gas impingement
Platform: AR-15 style rifle

Barrel Length: 16 inches
Barrel Material: Carbon steel
Barrel Twist Rate: 1:8″
Barrel Type: Free-floating barrel
Receiver Material: Aluminum
Finish: Black anodized finish
Stock: 6-position telescoping synthetic stock
Handguard: Free-floating M-LOK handguard
Trigger: SIG Matchlite trigger
Magazine Type: AR-15 / STANAG compatible detachable magazine
Magazine Capacity: 30 rounds
Sights: Optics-ready flat-top receiver
Muzzle Thread: 1/2×28 TPI
Overall Length: Approx. 30.8 inches
Weight: Approx. 7.0 lbs (with magazine configuration dependent)

Key Features

• .223 Remington / 5.56 NATO chambering
• 16-inch barrel for balanced performance
• SIG Matchlite trigger upgrade
• Free-floating M-LOK handguard
• 6-position adjustable stock
• Lightweight aluminum receiver design
• Direct impingement gas system
• 1:8 twist rate for versatile bullet compatibility
• AR-15 magazine compatibility
• 30-round magazine included
• Optics-ready Picatinny top rail
• Modular TREAD accessory compatibility
• Designed for range, training, and sporting applications

Package typically includes:

• SIG SAUER M400 TREAD COIL rifle
• 30-round magazine
• 6-position adjustable stock
• Free-floating M-LOK handguard
• SIG Matchlite trigger system
• Owner’s manual and safety documentation