Self Defense

Sig Sauer MCX Spear LT SBR

By: Dave Bahde

Excellence perfected

I was first acquainted with the Sig Sauer MCX Virtus when it was introduced in 2017 during a media event. I still have that rifle, along with a number of barrels, stocks, and handguards. It has proven to be absolutely reliable over several years and thousands of rounds, mostly 5.56mm but also some 300 Blackout. When given the chance to test the newest version, the MCX Spear LT SBR, I jumped on it. There has been a ton of chatter on this new rifle, so I was looking forward to seeing how it stacks up. My current MCX is also generally set up with an 11.5” barrel, as is this test model, so “new vs. old” comparisons could be easily drawn.

The lighter weight of the Spear LT compared to older MCXs can largely be attributed to a lighter-contour barrel. The handguard has also been lightened and slimmed down compared to previous versions and offers a much more solid interface for retaining zero with aiming devices. The factory flash suppressor doubles as a host for SIG’s current line of outstanding 3D-printed Inconel suppressors, of which the NG556-QD with the Clutch-Lok QD mount is shown here.

Sig Sauer MCX Spear LT 5.56mm SBR

While complaints about the Virtus were minimal, the biggest were overall weight, the need to use a specific trigger, and the size of the handguards. Right out of the box, it was pretty clear Sig Sauer addressed all of these nitpicks and more. At roughly a pound lighter, the weight change was immediately noticeable. Not only weight, but the balance is more centered, largely due to a lighter barrel profile. The handguard is much slimmer, better contoured, and attached to the receiver. While that makes it a tad harder to swap them out, there is no movement, providing a very solid feel. Stocks can still be swapped out, but the factory folding minimalist version on the SBR worked great; there are no adjustments, but it folds flat and allows firing while folded. Sig’s Flat Blade Match trigger is excellent, duty-capable, and predictable. If needed, it can be replaced with other AR-compatible triggers, but we’re not sure why you’d want to. The barrel is thinner and capped with their latest flash hider, which will accept the newest Sig Sauer suppressors. Controls are entirely ambidextrous, including a right-side bolt release (hold open) that sits in the perfect spot to be manipulated by the trigger finger. My test rifle was also equipped with the new Romeo 9T dual red dot sight. Incredibly robust, it allows you to swap between an independently-zeroed red circle-dot or green dot reticle with the push of a button, which is pretty handy, especially if you are making barrel or ammunition changes that would necessitate a change in zero.

The MCX dual-captured recoil spring — with a bolt operated via an adjustable short-stroke gas piston system — negates the need for a buffer tube, allowing for a folding buttstock. In place of a buffer tube is a Mil-Std 1913 Picatinny interface, accepting a multitude of stock or brace options (an 11.50” pistol version of the Spear LT is also available).

Range Time

Most testing was completed using Doubletap Ammunition’s 62-grain Solid Copper Hollow Point. Very soft and clean shooting, and it produced consistent one-inch or so groups in some challenging conditions at 100 yards. Most noticeable between old and new versions of the MCX was how little recoil and barrel movement there was with the Spear — especially impressive with just a flash hider. Changes have been made to the bolt/spring assembly, and they really helped in the recoil mitigation department. During rapid-fire strings of five rounds or more, the rifle settled in after round three and simply did not move. It’s as if it found a rhythm and just kept humming along. The faster the trigger was pulled, the steadier it became, producing one big hole at 15 yards from offhand. The right-side bolt release made reloads quick and simple. Upon initial inspection, there was no real reason to replace my Virtus, but after a few hours on the range, that opinion changed. It’s just that much more fun to shoot.

Controls on the Spear LT are fully ambidextrous, including the bolt catch, magazine release, safety selector, and charging handle. The factory Flatblade Match Trigger gets high marks across the board. QD sling swivel cups can be found on either side of the rear of the lower receiver and rear of the folding Minimalist Plus buttstock. Sig’s robust and technologically advanced ROMEO9T optic, which offers two independently zeroed reticles, was used throughout testing.

There certainly is a ton to like about the Romeo 9T, other than the price. At just under 4K, it is certainly outside most budgets, but it worked extremely well. Both the circle dot and green dot were very clear and crisp, even with my 65-year-old eyes. Glass is clear with a large field of view and a clean sight picture. To test its independently zeroed reticles, I zeroed the green dot at 50 yards with the 62-grain and the circle dot at 300 meters using 77-grain; it worked like a charm. All told, both the rifle and the optic are outstanding pieces of equipment at the top of their game. And, I liked the Spear LT enough to consider selling the Virtus to pick one up. For more information, contact Sig Sauer; Tel.: (603) 610-3000; Web: www.sigsauer.com