Build of the Month

Build of the Month: Rattlecan Lance

By Alex Fanning


First domesticated by humans 6 millennium ago, horses have been used in warfare for thousands of years. However, it wasn’t until the 3rd Century that javelins carried by Roman calvary would be replaced by the longer lance. A spear carried by charging mounted soldiers, the lance was used for thrusting rather than throwing, later evolving a protective plate during the medieval period to prevent the rider’s hand from sliding up the shaft upon impact. While effective against infantry, the lance was often a single-use weapon, and too heavy and slow to be used in melee combat if it survived impact without breaking.

Fast-forward to modern times and today’s soldiers are carrying a different type of spear.



Built on the legacy of the MCX Virtus, the SIG Sauer MCX-SPEAR LT blends shooter-friendly ergonomics for easy maneuverability with modern adaptability for versatile builds like our Rattlecan Lance. Incorporating the best features of the AR-15 but optimized for modern optics and accessories, suppressor use, and compact carry, the AR-18 pattern rifle punches above its weight.

New LT variant upgrades include a folding stock, lightened handguard, ambidextrous controls, and SIG’s flat blade match trigger for a performance feel any right or wrong-handed gunner can handle. Unloaded, the rifle weighs just 7.5 pounds.

Though we had to retorque the barrel and handguard upon receipt, the MCX-SPEAR LT was undeniably sturdy and understandably worthy of being selected as the U.S. Army’s service rifle. Accuracy also lived up to the high standards set by its price tag, as we were consistently hitting steel at 800 yards after a break-in period.

SIG SAUER M4 Style Stock

The beauty of the MCX lies within its upper receiver. Because its piston system and bolt design do not require a buffer tube to operate, users have more freedom when choosing a preferred buttstock. Originally equipped with a minimalist style stock, we swapped it for SIG’s M4 style stock with a folding picatinny adapter, specifically intended for the MCX/MPX. Shouldering the rifle from a high or low ready position and adjusting length of pull for different shooters was easier after the swap thanks to the larger butt and cheek pads and telescoping tube.

Magpul MOE K2-XL Grip

Enlarged by 25% for shooters with extra-large hands, Magpul’s MOE K2-XL Grip also caters to marksmen who prefer a more vertical grip angle for quick handling. While a unique texture and front and rear serrations aid grasp, an interior grip compartment provides utility for supplies on the go.


Swampfox Warhorse 1-6x FFP LPVO

Though horses and calvary have long been replaced in modern warfare, our Warhorse 1-6x FFP LPVO is a relatively new entry on the market. The first in our premier first focal plane (FFP) series of LPVOs, Warhorse was engineered to perform across its entire 1x to 6x magnification range for seamless transitions to maximize speed and precision. Its push/pull locking elevation turret with zero reset, capped windage turret, and 12 illumination settings provide further versatility for shooting in any light or battlefield condition.

Available with our Dragoon MOA or MIL reticle, we chose the latter for this build. At 1x, its simple design provides rapid targeting with an illuminated horseshoe and center dot. Zoom to 6x, and a precise MIL tree emerges, optimized for longer-distance shots. Crucially, as an FFP reticle, subtensions adjust in real-time with magnification changes, providing accuracy regardless of power.

Mounting to the MCX-SPEAR LT, our Hostile Engagement Mount provides a lightweight cantilever design with four 45-degree offset ring mounts for RMR footprint red dots like our Liberty II, Justice II, or Kraken – though we opted not to include a secondary optic.


SureFire SOCOM556-MINI2

A balance between size and performance, the SureFire SOCOM556-MINI2 checks both boxes, measuring just 5” and weighing in at 15 oz. Optimized for 14.5”and longer barrels on standard AR platforms, its internal baffling helps minimize back pressure and carbon going back into the gun but isn’t as good as a flow through suppressor. While its internals were far from clean after a full day on the range, the MINI2 did a great job keeping the sound forward and dust and dirt down when firing from prone.

Weapon Light

SureFire M640DFT-PRO Turbo Scout Pro

SureFire is well known for their weapon lights, and just like the MINI2, the Turbo Scout Pro did not disappoint. Its bright 700 lumens and long-range throw is perfect for target identification, offering 100,000 candela on a full battery with little drop off when switching to CR123 batteries. The light head is equipped with a reflector that balances between a sharp light beam and a spill of less intense light for broader awareness.

Further enhancing our Scout Light's functionality and ensuring peak control, we integrated a SureFire Scout Light TailCap assembly with UNITY Tactical’s ModButton Lite. Its momentary-only activation and low-profile design make it easy to operate without being obtrusive to hand placement when firing.


BCM Kinesthetic Angled Grip

While the new MCX-SPEAR LT handguard is lighter than its larger and heavier predecessor, its thinner profile can make getting a tight purchase more difficult for shooters with bigger hands. This is where the BCM Kinesthetic Angled Grip (KAG) comes in. Its forward rake design helps users achieve an ideal C-clamp on the rifle while its texture, both at the front and rear, ensures a steady grip.


Rust-Oleum Camouflage Spray Paint

Of course, no battle rifle is complete without a custom paint job. With a durable Coyote finish as a canvas, we used spray paint and netting to emphasize the field-worn look and really make this build our own. Rust-Oleum’s Specialty Camouflage Spray Paint is our go-to and offers great flat colors, like Army and Forest Green, Khaki, Sand, and Earth Brown.

And before you ask – spray painting or hard coating your Swampfox optic does not void warranty, so long as the optic’s function and performance are not impacted. Just tape off your lenses and be careful not to get paint in moving components like the rear diopter, magnification assembly, and turrets.

Why We Like It

Through multiple generations, the MCX platform has come a long way since first released in 2015. Having shot all three in similar configurations to this build, the MCX-SPEAR LT combines all generational advancements into one rifle.

Our Warhorse LPVO complements its accuracy potential with an FFP Dragoon reticle, and performance of the SureFire MINI2 for its size is hard to beat while also withstanding tough abuse. Combined with the SureFire Scout weapon light and other ergonomic upgrades, the Rattlecan Lance is a spear built for modern combat – horse optional.