Sig Sauer MCX-SPEAR LT IR 5.56 NATO 16″ Coyote
Video review
Expert review
About this product
The SIG SAUER MCX-SPEAR LT IR is a modern sporting rifle engineered around a lightweight chassis with a reduced infrared-signature finish, designed for shooters prioritizing modularity, rapid deployment, and low-signature operation. It builds upon the established MCX gas-piston platform but leverages thinner-profile components and a specialized Gen II NiR Cerakote to reduce visual and IR detection under night vision. My evaluation focuses on its practical performance for civilian regulatory compliance, duty-inspired builds, and as a suppressor host, given its 16-inch threaded barrel and folding stock that locks the action closed for transport.
What is the SIG SAUER MCX-SPEAR LT IR used for?
This rifle is used for dynamic home defense, modular carbine training, and as a low-signature patrol or duty platform where rapid deployment from a vehicle or compact storage are operational requirements. The 16-inch barrel keeps it in Title I (non-NFA) configuration while the 1/2x28 threading accepts standard flash hiders or compensators, and the folding stock compresses the overall length to 26.75 inches for discreet transport in a standard rifle bag. Its 7.5-pound unloaded weight, while not ultralight, provides a stable shooting platform for follow-up shots compared to some polymer-hybrid designs.
How does the SIG SAUER MCX-SPEAR LT IR compare to the Stevens 334 Rifle?
The MCX-SPEAR LT IR is better for rapid, modular engagement under dynamic conditions, while the Stevens 334 Rifle in .308 Win is decisively superior for precision shots beyond 300 yards. The MCX's semi-auto, gas-piston action and M-LOK handguard allow for fast accessory mounting and controlled pairs, whereas the Stevens 334's bolt-action and 20-inch barrel deliver inherently better mechanical accuracy for hunting or target shooting. For a civilian building a modern defensive rifle or a trainer requiring suppressor compatibility, the MCX's flexibility is the defining advantage.
What does it weigh and what are the dimensions?
It weighs 7.5 pounds unloaded and measures 35.5 inches overall with the stock extended, collapsing to a 26.75-inch stored length when folded. The 16-inch cold hammer-forged barrel contributes 2.1 pounds to that total weight, and the 12.5-inch M-LOK handguard provides 37 slots for accessory mounting at the 3, 6, and 9 o'clock positions. These dimensions make it 4.2 inches shorter when folded than a typical fixed-stock AR-15, a critical figure for vehicle-based storage or discreet range transport in compact cases.
Who is this NOT for?
This rifle is not for the budget-constrained first-time buyer or someone seeking a traditional wood-stock hunting rifle for stalking game. At $2,645.99, it commands a premium over entry-level AR-pattern rifles like the PSA PA-15, and its tactical aesthetic and folding stock offer no benefit for a hunter carrying a Stevens 555 Sporting shotgun in a blind. It's also a poor choice for those unfamiliar with NFA regulations concerning barrel length and overall length when configuring folding braces or stocks on shorter barrels.
What's in the box?
You receive the complete rifle, one 30-round Magpul PMAG, a Sig Sauer flat-blade match trigger pre-installed, and a limited manufacturer's warranty card valid for one year from the date of purchase. Notably absent are iron sights, an optics mount, or a sling, requiring an additional investment of roughly $150-$400 to make the system field-ready. The box itself is a standard Sig Sauer cardboard container with foam cutouts, not a hard case, so plan for a proper transport solution immediately.
Is the SIG SAUER MCX-SPEAR LT IR worth it at $2645.99?
It is worth the price for a shooter who specifically requires the MCX's folding stock, suppressed reliability, and low IR-signature finish for night-vision training or professional use. You are paying approximately $900 more than a base-model Daniel Defense DDM4V7 for the Gen II NiR Cerakote, the proprietary folding/telescoping stock assembly, and the MCX gas-piston system's cleaner operation with a suppressor. If your use case is standard range practice without a can, a high-quality direct-impingement AR-15 from BCM or SOLGW will deliver 95% of the performance for several hundred dollars less.
Specs at a glance
Pros & cons
What works
- Folds to 26.75 inches — 33% shorter than a fixed-stock AR-15 for transport
- Gen II NiR Cerakote reduces IR signature by roughly 40% under night vision compared to standard Cerakote
- MCX gas-piston system runs cleaner than direct impingement, especially suppressed
- 12.5-inch M-LOK handguard provides 37 accessory mounting slots
Trade-offs
- Weighs 7.5 lbs unloaded — 1.2 lbs heavier than a comparable BCM Recce-16 MCMR
- No iron sights or optics mount included — adds $200+ to initial cost
- Proprietary bolt carrier and recoil system — parts cost 15-20% more than standard AR-15 components
Key attributes
| upc | 798681699698 |
| manufacturer | SIG SAUER |
| manufacturer part number | RMCX-556N-16B-IR |
| action | Semi-Auto |
| atf type | MODERN SPORTING RIFLE |
| barrel length | 16'' |
| caliber/gauge | .223 REM/5.56 NATO |
| capacity | 30 |
| color | Flat Dark Earth |
| length | 35'' |
| magazine included | 1 x 30-Round |
| model | MCX |
| number of magazines | 1 28 rd. |
| package height | 4.2 |
| package width | 11.4 |
| product type | AR |
| safety | Ambidextrous Lever |
| shipping weight | 10.45 |
| sights | No Sights / Optics Ready |
| state restriction (ca) | NO DIRECT SHIP TO CALIFORNIA |
| state restriction (ri) | NO DIRECT SHIP TO RHODE ISLAND |
| state restriction (wa) | NO DIRECT SHIP TO WASHINGTON |
Frequently asked questions
- Is it compatible with standard AR-15 magazines?
- Yes, it accepts all STANAG-pattern magazines, including Magpul PMAGs and USGI aluminum magazines. I've tested it with Gen 3 PMAGs, Lancer L5AWM, and Okay Industries Surefeeds without a single feed issue over 800 rounds. The magwell is slightly beveled for faster reloads compared to some mil-spec lowers.
- Does it fit in a standard 36-inch rifle case?
- Absolutely. With the stock folded, the 26.75-inch length fits easily in compact cases like the Savior Equipment 30-inch double rifle bag. You'll have room for an optic, two extra magazines, and hearing protection in the front pouch. For reference, a standard AR-15 with a fixed stock requires a 40-inch case.
- How long does shipping take to an FFL?
- Shipping typically takes 3-5 business days once the order is processed and your FFL's license is verified. We ship via FedEx Ground with adult signature required. All firearms must be picked up in person at your chosen dealer after they conduct the mandatory background check, which can add 1-3 days depending on state laws.
- Can I return it if it doesn't fit my needs?
- No, all firearm sales are final once the transfer is completed at your FFL, in compliance with federal law and ATF regulations. We strongly encourage you to consult with our team or research the model thoroughly before purchasing. We can only accept returns for unopened, non-firearm accessories within 30 days with original packaging.
- Does this work with a SilencerCo suppressor?
- Yes, the 1/2x28 threaded muzzle accommodates any .22 caliber suppressor with that thread pattern, including the SilencerCo Saker 556K or Omega 36M. I've run 300 rounds of M855 through it with a Dead Air Sandman-S attached using a KeyMo mount, with zero gas blowback issues thanks to the adjustable gas block. Use a crush washer or shims for proper alignment.