
Availability: In Stock
Current Stock: Out of stock
The Sig Sauer MCX-SPEAR LT IR is a 5.56mm piston-driven pistol built on the proven platform trusted by elite military units worldwide. With its 11.5-inch cold hammer-forged barrel, threaded for suppressors, and Cerakote Gen II IR coating, this compact semi-auto delivers serious capability in a package engineered for modularity, reliability, and thermal discipline. Whether you're building a suppressed home-defense rig, testing a short-stroke platform, or exploring what makes the MCX a special-operations favorite, the LT IR brings genuine performance to the pistol category without the hype.
The IR designation refers to the reduced infrared signature offered by the Gen II FDE Cerakote finish—a practical advantage if thermal optics or night operations matter to your mission. That durability-focused coating also guards against corrosion in harsh field conditions, so your gun stays reliable when it counts. The adjustable gas system lets you tune the action to your ammo and suppressor setup, while the ambi controls and flat-blade trigger keep the platform intuitive for shooters of either hand. Cold hammer-forged carbon steel barrel, M-LOK accessory rail, and a folding PCB brace round out a genuinely modular design.
At 6.68 pounds (with the included 30-round polymer magazine), the MCX-SPEAR LT IR trades some heft for compactness—folding to 26.25 inches overall when the brace is collapsed. The 1:7 twist rate stabilizes a full range of 5.56 loads, and the QD suppressor-ready flash hider (Rocksett-secured) means a can fits without adapters. This isn't a bargain-bin plinker; it's a serious, piston-driven platform with a track record of standing up to hard use.
Sig Sauer engineered the MCX family for interchangeable barrels and a truly ambidextrous controls layout, so you can adapt it as needs evolve. If you want a short-barreled, suppressor-ready semi-auto rifle that doesn't sacrifice ergonomics or reliability, the MCX-SPEAR LT IR is a rig worth considering.
| Caliber | 5.56 NATO |
| Barrel Length | 11.5 inches |
| Barrel Material | Cold Hammer Forged Carbon Steel |
| Twist Rate | 1:7 |
| Thread Pitch | 1/2–28 tpi |
| Action | Semi-Automatic |
| Operating System | Gas Piston |
| Gas System | Adjustable |
| Receiver Finish | Cerakote Gen II NiR FDE |
| Trigger Type | SIG Flat Blade Match |
| Trigger Trigger | Flat |
| Grip | Polymer |
| Handguard | Lightweight Alloy |
| Rail System | M-LOK |
| Stock/Brace | PCB Folding Brace |
| Magazine Type | AR-15 Compatible |
| Magazine Capacity | 30 rounds (one included) |
| Magazine Material | Polymer |
| Controls | Fully Ambidextrous |
| Forward Assist | Yes |
| Flash Hider | SIG QD Suppressor-Ready (Rocksett-secured) |
| Overall Length | 29.75 inches |
| Folded Length | 26.25 inches |
| Width | 2.9 inches |
| Height | 7.5 inches |
| Weight | 6.68 pounds (with magazine) |
Yes. The rifle accepts AR-15 compatible magazines. One 30-round polymer magazine is included.
Yes. The 11.5-inch barrel is threaded 1/2–28 tpi and features a QD suppressor-ready flash hider, so a can attaches directly without adapters.
The Cerakote Gen II IR coating reduces the firearm's infrared signature under thermal or night optics while providing superior wear and corrosion resistance in harsh field conditions.
The PCB folding brace collapses the rifle to 26.25 inches overall length, down from 29.75 inches when the brace is extended.
The MCX-SPEAR LT IR features an adjustable gas system, allowing you to tune the action to your ammunition choice and whether you're running a suppressor. This helps optimize reliability and control in various configurations.

SKU: 198466857 • Weight: 8.5oz



Availability: In Stock
Current Stock: Out of stock
The Sig Sauer MCX-SPEAR LT IR is a 5.56mm piston-driven pistol built on the proven platform trusted by elite military units worldwide. With its 11.5-inch cold hammer-forged barrel, threaded for suppressors, and Cerakote Gen II IR coating, this compact semi-auto delivers serious capability in a package engineered for modularity, reliability, and thermal discipline. Whether you're building a suppressed home-defense rig, testing a short-stroke platform, or exploring what makes the MCX a special-operations favorite, the LT IR brings genuine performance to the pistol category without the hype.
The IR designation refers to the reduced infrared signature offered by the Gen II FDE Cerakote finish—a practical advantage if thermal optics or night operations matter to your mission. That durability-focused coating also guards against corrosion in harsh field conditions, so your gun stays reliable when it counts. The adjustable gas system lets you tune the action to your ammo and suppressor setup, while the ambi controls and flat-blade trigger keep the platform intuitive for shooters of either hand. Cold hammer-forged carbon steel barrel, M-LOK accessory rail, and a folding PCB brace round out a genuinely modular design.
At 6.68 pounds (with the included 30-round polymer magazine), the MCX-SPEAR LT IR trades some heft for compactness—folding to 26.25 inches overall when the brace is collapsed. The 1:7 twist rate stabilizes a full range of 5.56 loads, and the QD suppressor-ready flash hider (Rocksett-secured) means a can fits without adapters. This isn't a bargain-bin plinker; it's a serious, piston-driven platform with a track record of standing up to hard use.
Sig Sauer engineered the MCX family for interchangeable barrels and a truly ambidextrous controls layout, so you can adapt it as needs evolve. If you want a short-barreled, suppressor-ready semi-auto rifle that doesn't sacrifice ergonomics or reliability, the MCX-SPEAR LT IR is a rig worth considering.
| Caliber | 5.56 NATO |
| Barrel Length | 11.5 inches |
| Barrel Material | Cold Hammer Forged Carbon Steel |
| Twist Rate | 1:7 |
| Thread Pitch | 1/2–28 tpi |
| Action | Semi-Automatic |
| Operating System | Gas Piston |
| Gas System | Adjustable |
| Receiver Finish | Cerakote Gen II NiR FDE |
| Trigger Type | SIG Flat Blade Match |
| Trigger Trigger | Flat |
| Grip | Polymer |
| Handguard | Lightweight Alloy |
| Rail System | M-LOK |
| Stock/Brace | PCB Folding Brace |
| Magazine Type | AR-15 Compatible |
| Magazine Capacity | 30 rounds (one included) |
| Magazine Material | Polymer |
| Controls | Fully Ambidextrous |
| Forward Assist | Yes |
| Flash Hider | SIG QD Suppressor-Ready (Rocksett-secured) |
| Overall Length | 29.75 inches |
| Folded Length | 26.25 inches |
| Width | 2.9 inches |
| Height | 7.5 inches |
| Weight | 6.68 pounds (with magazine) |
Yes. The rifle accepts AR-15 compatible magazines. One 30-round polymer magazine is included.
Yes. The 11.5-inch barrel is threaded 1/2–28 tpi and features a QD suppressor-ready flash hider, so a can attaches directly without adapters.
The Cerakote Gen II IR coating reduces the firearm's infrared signature under thermal or night optics while providing superior wear and corrosion resistance in harsh field conditions.
The PCB folding brace collapses the rifle to 26.25 inches overall length, down from 29.75 inches when the brace is extended.
The MCX-SPEAR LT IR features an adjustable gas system, allowing you to tune the action to your ammunition choice and whether you're running a suppressor. This helps optimize reliability and control in various configurations.
SKU: 198466857 • Weight: 8.5oz
