--- title: "Sig Sauer SIGM400SDI X-Series 5.56 NATO | Rifles" description: "Sig Sauer SIGM400SDI X-Series 5.56 NATO Semi Auto AR15 Rifle - M-LOK - Black. Click for full product details. Shop KYGunCo for quality firearms & accessories." canonical_url: "https://www.kygunco.com/product/sig-sauer-rm400-sdi-16b-p-sigm400-sdi-5.56-16-x-series-30rd-black" meta: author: KYGUNCO "og:description": "Sig Sauer SIGM400SDI X-Series 5.56 NATO Semi Auto AR15 Rifle - M-LOK - Black. Click for full product details. Shop KYGunCo for quality firearms & accessories." "og:image": "https://cdn.kygunco.com/assets/products/221472/thumbnail.jpg?v=1713455747" "og:image:height": "500" "og:image:width": "500" "og:title": "Sig Sauer SIGM400SDI X-Series 5.56 NATO | Rifles" --- > Index of every page on this site: [llms.txt](https://www.kygunco.com/llms.txt) [Home](https://www.kygunco.com/) / [Shooting](https://www.kygunco.com/category/shooting) / [Guns](https://www.kygunco.com/category/shooting/guns) / [Rifles](https://www.kygunco.com/category/shooting/guns/rifles) / [Semi-Auto](https://www.kygunco.com/category/shooting/guns/rifles/semi-auto) / SGS-RM400-SDI-16B-P ![Main product image](https://static.kygunco.com/cdn-cgi/image/f=auto,w=600/assets/products/221472/main.jpg?v=1713455747) For illustration purposes only, this image may not be an exact representation of the product. # SIG SAUER SIGM400SDI X-Series 5.56 NATO 16" 30rd - Black 5.0 ** ** ** ** ** [1 review](#reviews) $1,499.99 ** 5 interest-free payments of **$300** with ![Sezzle logo](https://www.kygunco.com/brands/sezzle.svg) ** ![Credova logo](https://www.kygunco.com/brands/credova.svg) As low as **$183.77**/month with ![Credova text logo](https://www.kygunco.com/brands/credova-text.svg) ** Online In Store ** Free Shipping Enjoy delivery to the Lower 48 States at no cost. ** Ships To FFL Dealer Fulfilled by a partner warehouse. ** Partner Fulfilled ** Check Local Restrictions Not sure whether this item can be shipped to your area? Enter your ZIP code for a quick check. Almost gone. Order now before it sells out. Item # 221472 Style RM400-SDI-16B-P UPC 798681664634 Condition New Manufacturer [Sig Sauer](https://www.kygunco.com/brand/sig-sauer) Model SIGM400SDI Hand Right Hand Finish Black Round Capacity 30 Caliber 5.56 NATO Action Semi-Auto Barrel Length 16 in Sig Sauer M400 SDI XSERIES Rifle, 5.56mm 16" Barrel. Designed with additional features over the original M400 Tread, this XSERIES SDI M400 from Sig Sauer boasts a 16" barrel, a black anodized finish, a lightning cut upper/lower and is chambered for 5.56x45mm. The barrel is cut with 1/2" x 28 TPI threads with a hybrid compensator / flash hider installed. The M-LOK handguard features a clamping system for lower deflection and the SDI M400 offers an ambidextrous mag catch, bolt release, safety and charging handle. A SIG flat blade match trigger is installed as well as a Magpul SL 6 position stock. The M400 SDI X-SERIES is built to be a sharply upgraded rifle right out of the box; no need to worry about those small post-purchase upgrade projects. As with all Sig rifles, this model is built to perform and is ideal to customize to your comfort, shooting and situational needs. The SIG SAUER M400-SDI XSERIES packs a rich set of features and upgrades into the M400 platform delivering an advanced performance rifle right out of the box. The M400 XSERIES lower features fully ambidextrous controls, including bolt catch & release, selector switch, charging handle and mag release. Also unique to the XSERISE is a precision machined lightning cut upper and lower with a handguard clamp system designed to minimize deflection when using mounted accessories. Other features include a hybrid flash hider/compensator, 2-Stage Matchlite Trigger and Magpul SL Telescoping Stock. **SPECIFICATIONS** - CALIBER 5.56 NATO - CAPACITY 30 - OPERATING SYSTEM Direct Impingement - MAG TYPE AR-15 - FRAME MATERIAL Aluminium Alloy - FRAME FINISH Black Anodized - ACCESSORY SYSTEM M-LOK - TRIGGER TYPE SIG Flat Blade Match - BARREL LENGTH 16 in (406 mm) - BARREL MATERIAL Chrome / Moly Steel - BARREL THREADS 1/2" x 28 TPI - MUZZLE DEVICE Hybrid Comp / Flash Hider - TWIST RATE 1:7" - STOCK TYPE 6-Pos Magpul SL - OVERALL LENGTH 33.5 in (851 mm) - OVERALL WIDTH 2.8 in (70 mm) - HEIGHT 7.5 in (191 mm) - WEIGHT 7 lbs (3.18 kg) ** WARNING: This product contains chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to [www.p65warnings.ca.gov](https://www.p65warnings.ca.gov). ## Frequently Bought Together 5.0 ** ** ** ** ** 1 review ** ** ** ** ** 1 ** ** ** ** ** 0 ** ** ** ** ** 0 ** ** ** ** ** 0 ** ** ** ** ** 0 ## Reviews ** Verified Customer Great buying experience and excellent rifle 1/12/2024 ** ** ** ** ** ## Don't Forget Your Ammo ```json {"@context":"https://schema.org","@graph":[{"@id":"https://www.kygunco.com/#website","@type":"WebSite","description":"Shop KYGUNCO for firearms, ammo, accessories, parts, and outdoor gear at low prices with fast, easy nationwide shipping.","name":"KYGUNCO","url":"https://www.kygunco.com/","publisher":{"@id":"https://www.kygunco.com/#/schema/organization/kygunco"}},{"@id":"https://www.kygunco.com/product/sig-sauer-rm400-sdi-16b-p-sigm400-sdi-5.56-16-x-series-30rd-black#webpage","@type":"WebPage","description":"Sig Sauer SIGM400SDI X-Series 5.56 NATO Semi Auto AR15 Rifle - M-LOK - Black. Click for full product details. 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