Sig Sauer
Sig Sauer M400-SDI Sentry Rifle 5.56 NATO 30rd Magazine 16" Barrel Black with Romeo5 Gen II Foxtrot
Product Details
The M400-SENTRY offers a ready-to-go solution for the most discerning shooters combining the proven capabilities of the M400-SDI X platform with the multi-purpose functionality of the ROMEO5 GENII red dot FOXTROT-MSR Full Size Light and a vertical foregrip. This combination of standardized features makes the M400-SENTRY an out-of-the-box solution for home/personal defense advanced training or recreational shooting.
Like other rifles in the series the M400-SENTRY was developed based on the direct input of professional instructors at SIG SAUER Academy. Their decades of combined experience and personal knowledge ensures that all M400 rifles are designed to meet the highest standards of reliability and performance.
Adding to the advanced capabilities of the M400 platform is the pre-installed ROMEO5 GENII red dot FOXTROT-MSR Full Size Light and vertical foregrip. With its 1x aiming solution and crisp 1 MOA dot the ROMEO5 GENII provides over 40000 hours of estimated runtime compliments of SIG SAUER’s motion-activated MOTAC design. The ROMEO5 GENII is IPX7 waterproof rated and its fully-multicoated lenses ensure visibility in all environments. Top mount illumination controls provide ease of use by both left and right-handed shooters.
For added visibility in low-light conditions the FOXTROT-MSR Full Size Light with its 1250 Lumens and 33000 Candela clearly illuminates targets while maintaining ease of use and accessibility. The M400-SENTRY is also furnished with a vertical foregrip on the free-floating handguard enabling greater control of the rifle regardless the shooting position.
FEATURES INCLUDE:
- ROMEO5 GENII Red Dot FOXTROT-MSR Full Size Light and Vertical Foregrip
- Fully Ambidextrous Controls (Safety Charging Handle Bolt Catch & Release)
- Free-Floating M-LOK Forend
- (3) M-LOK Rail Covers Included
- SIG 2-Stage Matchlite Duo Trigger
- 16” Chrome/Moly Steel Barrel with 1:7 Twist Rate
- 6-Position Magpul MOE-SL Stock
- Low Profile Gas Block with Mid-Length Operating System
Specifications
| Brand | Sig Sauer |
|---|---|
| UPC | 798681716128 |
| Caliber | 5.56 NATO / .223 |
| Action | Semi-Auto |
| Color / Finish | Black |
| Barrel Length | 16" |
| Capacity | 30 rounds |
| Weight | 10.8 lb |
| Condition | New |
Buying this item
- Can I buy the Sig Sauer M400-SDI Sentry Rifle 5.56 NATO 30rd Magazine 16" Barrel Black with Romeo5 Gen II Foxtrot 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-SDI Sentry Rifle 5.56 NATO 30rd Magazine 16" Barrel Black with Romeo5 Gen II Foxtrot?
- You must be 18 or older with valid government ID for rifles and shotguns (21+ for handguns).
- Is the Sig Sauer M400-SDI Sentry Rifle 5.56 NATO 30rd Magazine 16" Barrel Black with Romeo5 Gen II Foxtrot 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
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Ammo, magazines and optics matched to Sig Sauer M400-SDI Sentry Rifle 5.56 NATO 30rd Magazine 16" Barrel Black with Romeo5 Gen II Foxtrot. Everything here ships to your door or is ready at pickup.
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5.56 NATO / .223 ammunition
Same caliber as this firearm.
Magazines that fit
Matched by caliber and Sig Sauer fit.
Optics for this rifle
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