Rifle Review: MCX Virtus From SIG SAUER

I attended a two-day seminar hosted at the SIG SAUER Academy. The purpose of the excursion was an in-depth analysis of the MCX Virtus. I will admit to some initial skepticism involving the MCX Virtus. This stemmed from already being impressed with the original MCX platform. This skepticism was not quelled when it was found out that barrels and other components were not interchangeable between the two. How could the MCX Virtus be worthy of supplanting the original MCX? — it had only been on the market for a few years? SIG mulled over the same question. SIG correctly decided the advancement of the MCX platform could not be held back. The logistics of introducing the MCX Virtus platform was worth it.

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SIG MCX Virtus disassembled during barrel change procedure.

Part of the SIG decision with the MCX Virtus was the haunting feeling the MCX had never been fully defined/explained to the shooting public. Yes, certain Tier One units realized what it offered. After all, it was their solicitation request that brought the MCX to life in the first place. This same elite operator feedback is what drove the Virtus improvements. The MCX is not just another AR platform. It is a distinct stand-alone system with features justifying this claim. The folding stock and modularity are big indicators of this. The MCX Virtus takes things one step further.

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The Virtus improvements consist of the tapered lug bolt group (a large reason why MCX and MCX Virtus are not compatible), two-stage SIG Matchlite Duo trigger, M-Lok handguard, gas location shifted thicker receivers and barrels. All of the improvements were driven by SOCOM contract requests that sought to increase accuracy, modularity, and durability. Stories were shared at the SIG Academy of how SIG SAUER MCX Virtus would be submitted for certain trials with all associated gear arriving in one hard case. I am speaking of different calibers (5.56mm and .300BLK), barrel lengths, handguards, optics, and suppressors. Competitors would be wheeling in multiple cases with uppers having to be set up independently to meet desired trial parameters versus just switching out specific components. SIG SAUER has created itself an advantage by being a total system provider — weapons, optics, suppressors, ammunition, and other accessories.

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Training at SIG SAUER ACADEMY with MCX Virtus.

The MCX Virtus represents the latest approach to rifle methodology. The MCX Virtus is a continuation of the MCX approach blending adaptability of caliber and configuration. The MCX spawned from SOCOM request to develop a lightweight (7lbs. or less), compact (folding stock multiple barrel length options) multi-caliber (5.56mm & .300BLK) rifle that from the beginning was intended to be suppressed.

MCX Virtus operating controls and basic ergonomics are similar to the ever so prevalent AR15 — an important consideration for training/orientation purposes. AR-like ambidextrous magazine and bolt release along with centrally located non-reciprocating charging handle will be instantly familiar to any AR user. A flat top upper allows for any AR type sighting system. The MCX Virtus uses AR-type fire control system and magazines. However, the bolt carrier group is different. This stemmed from the initial user’s request to use a folding stock in lieu of a typical AR buffer tube set up. SIG installed dual recoil springs above the bolt carrier group. Due to recoil spring placement, the charging handle sits slightly higher on the MCX compared to an AR. Not only did the dual recoil springs enable the folding stock, but had other benefits in terms of smoother/softer recoil impulse, eliminate buffer tube wear associated with AR piston driven rifles, and increased overall reliability/durability.

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MCX Virtus is both modular and ambidextrous.

The MCX operates via short-stroke gas piston system. The MCX Virtus gas port locations change depending on caliber chosen. Much of the SIG SAUER MCX Virtus development focused on finding proper placement of the gas ports to optimize reliability. The MCX Virtus features an adjustable gas regulator with the first position for normal operation, while the second position is for when using a sound suppressor. As stated previously, the MCX Virtus was designed to accommodate suppressor use — an obvious reflection of its adaptation to current trends in fighting rifles.

The Fun Part

The two days at the SIG SAUER Academy started with a specific MCX Virtus and support kit assigned to each participant. The kit consisted of both 5.56mm and .300BLK barrels of different lengths, handguards, buttstocks, SIG SAUER suppressors, and SIG SAUER optics such as the Tango 6 1-6x, Romeo 4T red dot, Juliet magnifier etc. First up was the Virtus configured with 16″ 5.56mm barrel and SIG SRD556-SD suppressor mounted via SIG Taper-Lok muzzle device. SIG SAUER Tango 6 1-6x optic was mounted. SIG SAUER Elite 77-grain OTM Match was used during the testing. After a brief sight confirmation period, the SIG SAUER Academy instructors began walking the group back to different firing lines. This culminated back at the 750-yard line. The MCX Virtus combined with the previously mentioned accessories had no problems engaging 12″ and 6″ plates from the 750-yard line. 1.5 MOA or better accuracy is the norm for the MCX Virtus. The Tango 6 1-6x had the appropriate holdover hashes from 350 yards to 750 yards and beyond. The clarity needed in a 6x optic to engage 6” targets at 750 yards speaks for itself.

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SIG SAUER Tango 6 1-6x optic that proved nearly ideal companion with the MCX Virtus.

Another training evolution had the visiting group meet in a classroom to swap out barrels on their assigned MCX Virtus to a 9″ barrel in. 300BLK. A SIG SRD762-SD suppressor was installed. This literally took only minutes to do after receiving a short block of instruction. A SIG SAUER Romeo 4T red dot was mounted with a Juliet 3x magnifier also installed. Action at the range was CQB style showing off the potential of the .300BLK MCX Virtus, especially when suppressed.

Day Two started off with a “Hogan’s Alley” scenario involving multiple magazines changes moving between various firing points against a multitude of designated targets. Switching between shoulders was required based on firing positions. The MCX Virtus’s ergonomics and ambidextrous controls were really appreciated. The culminating training evolution consisted of a “Jungle Run” course involving multiple MCX Virtus configurations to show off its versatility. Long range engagement and then CQB targets proved easy to handle with the MCX Virtus. An interesting twist at the end was the chance to finish the stage with the new MCX Rattler (Stay tuned for more on the Rattler).

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A small sampling of the options available with the MCX Virtus — nearly 500 different configurations is possible between buttstocks, barrels, forends and so on.

At the beginning of my two days at SIG SAUER, I openly questioned if a new model MCX was really necessary. I was thinking of the owners who already invested in the original MCX. I was told the answer to my question would be self-evident after two hard days on the range. They were right! With a cumulative total of over 10,000 rounds fired the MCX Virtus proved to be everything its advertised to be. The real shame would have been if the improvements represented in the MCX Virtus had been withheld. SIG SAUER was willing to make the investment in retooling and enhancing the MCX with the Virtus. They were confident that what the MCX Virtus offered would validate their decision. I came away convinced they were correct. Performance is the quickest way to appeal to the shooting public — the MCX Virtus will have no problem proving its worth.

For more information, visit: www.sigsauer.com

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