Sig Sauer MCX SPEAR LT 5.56 NATO, 16 in Carbon Steel Barrel, FDE Cerakote, Short-Stroke Gas Piston, Folding Stock, 3 Mags
The Sig Sauer MCX SPEAR LT in 5.56 NATO brings the MCX architecture into a lightweight, fully ambidextrous rifle with premium features and a durable Gen II NiR FDE Cerakote finish. This configuration pairs a 16 inch cold hammer-forged, threaded barrel with a short-stroke gas piston system and an adjustable gas regulator, delivering a modern, adaptable platform with high-end controls and a clean, as-new presentation.
Condition
Overall Condition: As-new condition with no signs of prior handling beyond what's typical from inspection (see photos).
Bore Condition: New - As-new bore with no signs of use beyond factory testing.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: Presents as new with no handling wear noted; inspection shows no evidence of firing beyond factory testing.
What's Included
- SIG Sauer factory box (label: RMCX-556N-16B-LT)
- 3x 30rd Magpul PMAG GEN M3 Window polymer magazines (AR/M4 pattern)
- M-LOK polymer angled foregrip/handstop (installed)
The SPEAR LT series uses a short-stroke gas piston system with an adjustable gas regulator, offering a clean-running action and consistent performance. The MCX quick-change, multi-caliber architecture is built into the receiver marked SIG MCX MULTI-CALIBER, supporting the platform's modular design.
The 16 inch carbon steel barrel is cold hammer-forged and factory threaded 1/2-28, capped with a 3-prong flash hider. A 1:7 twist rate supports common 5.56 NATO projectile lengths and weights, and the threaded muzzle provides straightforward compatibility with 1/2-28 devices.
Controls are fully ambidextrous, including the manual safety, paddle-style magazine release, bolt catch, and charging handle. The SIG Matchlite Duo trigger is a two-stage, flat-faced unit that provides a precise break and predictable reset.
An aluminum free-float M-LOK handguard with integral QD sling sockets surrounds the barrel, and a full-length Picatinny top rail provides uninterrupted mounting space. No iron sights are installed from the factory.
The aluminum-alloy receiver wears a Gen II NiR FDE Cerakote finish to match the folding, skeletonized stock in FDE. Capacity is 30+1, and this rifle includes three PMAG GEN M3 Window magazines along with a factory-installed M-LOK polymer angled foregrip/handstop. Made in the USA; manufacturer part number RMCX-556N-16B-LT.