The SIG SAUER M400 SDI X is a semi-automatic modern sporting rifle built around a 16-inch cold hammer-forged barrel and optimized for reliable, repeatable performance. It features fully ambidextrous controls, a free-floating M-LOK handguard and a mid-length direct impingement gas system for smoother operation. The rifle is outfitted with SIG’s 2-stage Matchlite Duo trigger and a multi-position Magpul MOE-SL stock for ergonomic handling.
Key Specifications
- The action is Semi-Auto.
- Chambered in 5.56 NATO.
- The barrel measures 16 inches and is cold hammer-forged.
- The barrel material is chrome-moly (cold hammer-forged).
- The rifling twist rate is 1:7.
- It uses a mid-length direct impingement gas system.
- The free-floating handguard is an M-LOK aluminum design.
- The stock is a 6-position Magpul MOE-SL.
- It includes a SIG 2-Stage Matchlite Duo flat trigger.
- Includes one 30-round polymer magazine.
The M400 SDI X balances modern controls and durable construction for consistent performance across range use, training, and practical shooting applications. Thoughtful ergonomics, a free-floating M-LOK platform, and a match-grade trigger make it well suited to users seeking a reliable, configurable rifle for general sporting use.
Product information is supplied by the manufacturer and/or distributor and may be automatically formatted or enhanced using AI for clarity and consistency. While we strive for accuracy, specifications, features, and included items may change without notice. Always verify details using the manufacturer’s official documentation and the information shown on this product page before purchase or use.
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