Sig Sauer
Sig Sauer M400 Forge Concrete Gray Rifle 5.56 NATO 30rd Magazine 16" Barrel ROMEO-MSR GEN II Adjustable Stock M-LOK Handguard
Product Details
Features:
- TriggerTech 3.5 pound two-stage flat blade duty trigger
- 16" cold hammer forged barrel with mid-length gas system
- ROMEO-MSR Gen II 2 MOA red dot included
- Full-length free-floating M-LOK handguard
- Ambidextrous charging handle
- MAGPUL SL-K 6-Position adjustable stock
Specifications:
- FIREARM TYPE: Rifle
- CALIBER: 5.56 NATO
- SIGHTS: ROMEO-MSR GEN II w/2 MOA DOT
- BARREL LENGTH: 16 in [406.4 mm]
- BARREL MATERIAL: Cold Hammer Forged Steel
- TWIST RATE: 1:7
- THREADS: 1/2 in - 28 90 Degree Shouldered
- MUZZLE DEVICE: A2 Birdcage Flash Hider
- ACTION TYPE: Semi-Auto
- OPERATING SYSTEM: Mid-Length Direct Impingement
- STOCK TYPE: 6-Position Magpul SL-K
- GRIP TYPE: Reduced Angle
- TRIGGER TYPE: TriggerTech 3.5-Pound 2-Stage Flat Blade
- TRIGGER SHAPE: Flat
- MANUAL SAFETY: Ambidextrous
- FOREND TYPE: M-LOK Concrete Gray Cerakote
- ACCESSORY RAIL: M-LOK/Full-Length Picatinny
- MAG TYPE: AR-15
- MAGS INCLUDED: (1) 30rd Polymer Mag
- COLOR: Concrete Gray
- RECEIVER FINISH: Concrete Gray Cerakote
- OVERALL LENGTH: 35.5 in [901.7 mm]
- COLLAPSED LENGTH: 32.25 in
- OVERALL WIDTH: 2.7 in [68.58 mm]
- HEIGHT: 9.4 in [819.15 mm]
- WEIGHT: 6.8 lb [3084.43 kg]
Specifications
| Brand | Sig Sauer |
|---|---|
| UPC | 798681744183 |
| Caliber | 5.56 NATO / .223 |
| Action | Semi-Auto |
| Color / Finish | Gray |
| Barrel Length | 16" |
| Capacity | 30 rounds |
| Material | Steel |
| Weight | 9.9 lb |
| Condition | New |
Buying this item
- Can I buy the Sig Sauer M400 Forge Concrete Gray Rifle 5.56 NATO 30rd Magazine 16" Barrel ROMEO-MSR GEN II Adjustable Stock M-LOK Handguard online and have it shipped to me?
- Firearms cannot ship to your home. Buy it here and pick it up at Iron Valor Armory in Rocky Mount, NC after a NICS background check, or have it shipped to a licensed FFL dealer near you for their transfer fee.
- How old do I have to be to buy the Sig Sauer M400 Forge Concrete Gray Rifle 5.56 NATO 30rd Magazine 16" Barrel ROMEO-MSR GEN II Adjustable Stock M-LOK Handguard?
- You must be 18 or older with valid government ID for rifles and shotguns (21+ for handguns).
- Is the Sig Sauer M400 Forge Concrete Gray Rifle 5.56 NATO 30rd Magazine 16" Barrel ROMEO-MSR GEN II Adjustable Stock M-LOK Handguard in stock?
- Yes — live distributor inventory shows it in stock and it ships or is ready for pickup within 1–3 business days.
- What is the return policy?
- Non-firearm items may be returned within 30 days (a restocking fee of up to 15% applies if the packaging was opened). Firearms and ammunition are final sale once transferred, per federal law.
All firearm sales require background checks and compliance with federal, state, and local laws. You must be 21+ for handguns/stripped receivers and 18+ for long guns.
Frequently bought together
Complete the setup
Ammo, magazines and optics matched to Sig Sauer M400 Forge Concrete Gray Rifle 5.56 NATO 30rd Magazine 16" Barrel ROMEO-MSR GEN II Adjustable Stock M-LOK Handguard. Everything here ships to your door or is ready at pickup.
Adds the first item in each column · you can adjust in the cart
5.56 NATO / .223 ammunition
Same caliber as this firearm.
Magazines that fit
Matched by caliber and Sig Sauer fit.
Optics for this rifle
We mount and bore-sight for pickup.
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