Sig Sauer SIGM400 TREAD COIL 5.56x45mm NATO Semi-Automatic Rifle 16″ Barrel 30-Round

Sig Sauer SIGM400 TREAD COIL Rifle for Sale – Advanced Modular Performance

At Langston Ammunition Store, we proudly offer the Sig Sauer SIGM400 TREAD COIL rifle for sale—a high-performance AR-15 platform built with Sig’s legendary engineering and modular TREAD ecosystem. Designed for precision shooters, home defenders, and tactical enthusiasts, this rifle delivers next-level customization, reliability, and accuracy straight out of the box. Sig Sauer SIGM400 TREAD COIL rifle for sale online, Sig Sauer SIGM400 TREAD COIL rifle for sale near me

Key Features

✔ TREAD COIL Handguard System –

• 13.5″ M-LOK compatible for full accessory customization

• Lightweight yet rigid for improved heat dissipation

• Slim profile for comfortable handling

 Match-Grade Barrel –

• 16″ cold hammer-forged (1:8 twist)

• 5.56 NATO / .223 Rem chamber (shoots both)

• Mid-length gas system (smoother recoil impulse)

✔ Enhanced Controls –

• Ambi charging handle & safety

• TREAD enhanced trigger (clean 5.5-lb break)

• 6-position adjustable stock

✔ Optic-Ready & Suppressor-Compatible –

• Flat-top upper with Picatinny rail

• Threaded muzzle (1/2×28) for brakes or suppressors

Specifications

• Caliber: 5.56 NATO / .223 Rem

• Barrel Length: 16″ (mid-length gas)

• Overall Length: 32.5″–35.5″ (adjustable stock)

• Weight: 6.7 lbs (unloaded)

• Magazine Capacity: 30+1 (includes 1 Magpul PMAG)

• Handguard: 13.5″ TREAD COIL M-LOK

• Finish: Hardcoat anodized

Why the SIGM400 TREAD COIL?

• Sig Sauer Quality – Battle-proven reliability
• Unmatched Modularity – TREAD system allows easy upgrades
• Better Than Standard ARs – Smoother shooting with mid-length gas
• Ready for Optics/Lights – Full-length top rail & M-LOK slots

Perfect For

• Tactical Training – Balanced handling for CQB & mid-range

• Home Defense – Lightweight & maneuverable

• Competition Shooters – USPSA, 3-Gun ready

• First AR-15 Buyers – Easy to customize as skills grow

Included

• (1) 30-round Magpul PMAG

• TREAD COIL handguard tool

• Owner’s manual

The Sig Sauer SIGM400 TREAD COIL redefines the modern AR-15—available now at Langston Ammunition Store.