SIG M400 for Sale
Browse SIG M400 listings from verified sellers across the U.S. on GunsAmerica.
Quick Look
The SIG M400 was developed by SIG Sauer as an AR-style rifle platform for civilian and law enforcement use. Designed for modularity, performance, and value, it embraces the proven direct impingement system. The M400 enjoys solid popularity for range, home defense, and tactical applications.
Why It's a Top Choice
- Reliable direct impingement AR-15 rifle from SIG Sauer
- 5.56 NATO chambering with excellent parts compatibility
- Multiple models for duty, defense, or competition
- Free-floating M-LOK handguards on most variants
- Enhanced lower receiver geometry for better ergonomics
Key Variants
SIG M400 Tread
A budget-friendly variant with upgrade potential; ideal for first-time AR buyers.
SIG M400 SDI X
Enhanced version with ambidextrous controls and match-grade trigger; great for tactical users.
SIG M400 Predator
Tuned for hunting and long-range shooting with a precision barrel and optics-ready rail.
SIG M400 Elite
Premium model with upgraded furniture and internals; solid for duty or defensive roles.
SIG M400 Pro
Law-enforcement-focused offering with MIL‑SPEC features and dependable construction.
Competitor Comparison Table
| Feature | Sig M400 | Smith & Wesson M&P15 | Ruger AR-556 |
|---|---|---|---|
| MSRP | $949–$1,599 | $800–$1,000 | $699–$899 |
| Capacity | 30+1 | 30+1 | 30+1 |
| Weight | ~7.3 lbs | ~6.9 lbs | ~6.5 lbs |
| Optics-ready | Yes | Some models | Some models |
| Trigger type | MIL‑SPEC or match | MIL‑SPEC | MIL‑SPEC |
| Notable pro | High-end options and customization | Reliable and widely available | Excellent value for new shooters |
| Notable con | Higher price than basic ARs | Limited advanced features | Basic furniture and finish |
Best Use Cases
- Home defense carbine platform
- Law enforcement patrol rifle
- Tactical training and carbine courses
- 3-Gun and other competitions
- Recreational range use
FAQs
What is the twist rate of the Sig M400 barrel?
Most Sig M400 rifles feature a 1:7 twist rate, ideal for stabilizing heavier 62–77 grain bullets.
Can I customize the Sig M400 with aftermarket parts?
Yes, the M400 is compatible with most AR-15 standard parts including triggers, stocks, and rails.
How does the Sig M400 compare to a MIL‑SPEC AR-15?
The M400 meets or exceeds most MIL‑SPEC dimensions but often includes upgraded ergonomics and finish.
Prefer nearby results? Toggle to search local listings.
Sig Sauer M400 Tread Predator 5.56 16"
$1,099.00
Sig Sauer M400 Rose (RM400-16B-ROSE-R5-2
$1,499.99
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