SIG Sauer M400 5.56 NATO AR-15, 16 in Barrel, Troy Railed Handguard, Magpul MOE Furniture, Muzzle Brake, Flip-Up Rear Sight, Pelican 1700 Case, 3 PMAGs
This customized SIG Sauer M400 combines the forged 7075-T6 receiver set and 16-inch direct-impingement 5.56 NATO system with a Troy aluminum railed handguard, Magpul MOE stock and grip, and an aftermarket multi-port muzzle brake. It includes a Pelican 1700 hard case and three Magpul PMAGs. The bore is excellent, and overall condition is very good.
Condition
Overall Condition: Very good condition, showing only light, superficial signs of prior handling or use.
Bore Overall Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: There are minimal markings from previous handling and use. Please refer to the photos for a closer look at surfaces and small parts.
What’s Included
- Pelican 1700 hard case
- Three 30-round Magpul PMAG polymer STANAG-pattern magazines
- Troy aluminum railed handguard with circular vent holes (installed)
- Magpul MOE collapsible carbine stock (installed)
- Magpul MOE pistol grip (installed)
- Magpul B.A.D. Lever bolt catch extension (installed)
- Flip-up aperture rear sight on receiver (installed; brand unmarked)
- Multi-port muzzle brake/compensator (installed)
- Short Picatinny accessory rail section at 6 o’clock on handguard (installed)
- Ring-style sling loop mounted near front of handguard (installed)
The M400 foundation is a forged 7075-T6 aluminum receiver set with a hard-coat anodized finish. It retains core AR features including a forward assist, dust cover, and brass deflector. Markings include the SIG SAUER INC EXETER–NH–USA roll mark and SIG M400 5.56 NATO model/caliber. The upper receiver shows an “A” forging mark, and the integrated top rail is T-marked from T4 through at least T24.
The Troy aluminum handguard provides a full-length, T-marked top rail that mates cleanly with the receiver rail and uses circular vent holes for weight reduction and cooling. A short 6 o’clock Picatinny section is mounted for accessories, and a ring-style sling loop is positioned near the front of the handguard.
Ergonomics and controls are enhanced with Magpul MOE furniture, including the collapsible carbine stock and MOE pistol grip. A Magpul B.A.D. Lever is installed on the bolt catch to streamline right-hand bolt-lock and release functions.
Sighting is handled by a fixed A2-style front sight/gas block paired with a flip-up aperture rear sight on the receiver. The threaded barrel is fitted with an aftermarket multi-port muzzle brake/compensator.
This rifle uses the STANAG magazine interface with a stated 30+1 capacity and comes with three 30-round Magpul PMAGs. The platform is AR-15 pattern with semi-automatic, direct-impingement operation, and the top rail is T-marked for repeatable accessory placement.