SIG SAUER M400 SDI for Sale
Browse SIG Sauer M400 SDI listings from verified sellers across the U.S. on GunsAmerica.
Quick Look
The SIG Sauer M400 SDI is a modern AR-style rifle introduced to meet rigorous duty and personal defense needs. It emphasizes modularity and rugged reliability, built on a direct impingement system for practical performance. This model holds a respected place among mid-weight rifles favored by law enforcement and enthusiasts alike.
Why It's a Top Choice
- Reliable SIG direct impingement action
- Modular handguard and accessory options
- Precision barrel with reliable accuracy
- Ergonomic design for comfortable handling
- Good factory warranty and support
Key Variants
M400 SDI Patrol
A compact version with a 16" barrel ideal for patrol and duty use.
M400 SDI Piston
Featuring a piston system for reduced fouling, suited for extended use.
M400 SDI Carbine
Standard full-size 18" version built for versatility and range work.
Competitor Comparison Table
| Feature | M400 SDI | Ruger AR-556 | Smith & Wesson M&P15 Sport II |
|---|---|---|---|
| MSRP | $1,000–$1,200 | $700–$900 | $800–$1,000 |
| Capacity/Size | 30 rounds / 16–18" barrel | 30 rounds / 16" barrel | 30 rounds / 16" barrel |
| Weight | 6.8 lbs | 6.5 lbs | 6.5 lbs |
| Optics-Ready | Yes, Picatinny rail | Yes, Picatinny rail | Yes, Picatinny rail |
| Trigger Type | Mil-spec single-stage | Mil-spec single-stage | Mil-spec single-stage |
| Notable Pro | SIG quality control and precision | Affordable price point | Strong aftermarket support |
| Notable Con | Higher price than entry ARs | Basic furniture and finish | Slightly heavier than peers |
Best Use Cases
- Duty and law enforcement applications
- Personal defense and home protection
- Range training and marksmanship practice
- Light hunting where legal and appropriate
- Collectors valuing SIG design and quality
FAQs
Can I use standard AR-15 magazines with the SIG Sauer M400 SDI?
Yes, the M400 SDI accepts standard AR-15 magazines, facilitating wide aftermarket magazine compatibility.
What barrel lengths are available for the M400 SDI?
Common barrel lengths include 16 and 18 inches, balancing maneuverability and ballistic performance.
How does the direct impingement system affect maintenance?
Direct impingement requires regular cleaning but offers proven reliability and reduced weight compared to piston systems.
Prefer nearby results? Toggle to search local listings.
Sig Sauer M400 SDI XSeries RM400-SDI-16B
$1,534.99
Sig Sauer M400 SDI XSeries RM400-SDI-16B
$1,792.99
Sig Sauer M400 SDI XSeries RM400-SDI-16B
$1,792.99
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