Test: SIG Sauer MCX Virtus Sport in .223 Remington

AR-15s – either you love them or you can't stand them. However, people who have no love for these Black Guns should know that the market gets what the market wants. But the question is – and rightly so – what else can be new? Well, standstill means death, as the saying goes. And you can always do something better, even in the  AR-15 segment. This is what was probably behind it when SIG Sauer presented its new Virtus.

Questions and more questions to Armin Dobat from SIG Sauer

All4shooters was sent a rifle that takes the AR-15 to a new level. As is the case with journalistic reporting, a few questions arose after examination. Armin Dobat, Senior Director Product Management at SIG Sauer, was asked those questions.

All4shooters: What makes the Virtus something special?

Armin Dobat: Here are some points that make this model something special on the market. The MCX Virtus has no buffer tube. This results in a better recoil behavior. In other words, the rifle shoots more comfortably. It also makes the gun lighter and more flexible. Moreover, our designers revised the bolt locking lugs and made them tapered. This ensures a gentler cycling and increases service life. The barrel of the MCX Virtus is free-floating and forged, not only cold-hammered. Thus, the MCX Virtus ensures that points of contact does not affect accuracy. And it also ensures higher strength and significantly higher energy yield.

All4shooters: Is there any practical feedback from the market?  

Armin Dobat:  There is an initial feedback from the civilian market. After all, the MCX Virtus was introduced in Europe at the beginning of 2019. Reactions we received are consistently positive. The MCX Virtus has already proven its worth on the police and law enforcement market: as a new mid-range rifle, it is used among others by police units in Schleswig-Holstein and Berlin. The London Metropolitan Police also adopted the rifle.

SIG SAUER MCX Virtus with optics from the left.
A reinterpretation of the AR-15 system from SIG Sauer in the form of the MCX Virtus. Technical innovation meets perfect design here.

All4shooters: The original MCX existed only in the United States of America. What are the differences to the current generation of the MCX?

Armin Dobat:  The MCX Virtus in its current form is more suitable for the European market. The predecessor's KeyMod fore-end has been replaced with a more modern M-LOK fore-end, just as the buttstock is now more flexible. In addition, the military hard standard trigger has been replaced by a precise match trigger.

All4shooters: The model name of our test gun ends with the word "sport". But even hunters can purchase this rifle. Is this a future market for SIG Sauer?

Armin Dobat: What we are seeing is a growing interest by hunters in semi-automatic rifles. We are confident that the MCX Virtus will convince hunters of its qualities and will find its place among them. Regardless of whether you are a sports shooter or a hunter, once you fire  it you can't escape the fascination.

At SIG Sauer they are quite convinced of their gun – as can be expected from a firearms manufacturer. But it was also time to take a closer look at the rifle, of course.

MCX Virtus, the bare facts

 SIG SAUER MCX Virtus Sport with tele-fold stock
Foldable: the SIG Sauer MCX Virtus Sport features a tele-fold stock.

All4shooters received an MCX Virtus from SIG Sauer with a 16.6 inch / 421 mm long barrel in .223 Remington caliber. There is also a shorter version with a 11.5 inch / 292 mm long barrel. In both lengths, the barrels are chrome lined and phosphated on the outside. The barrel root is conical and the diameter at the muzzle measures 16.5 millimeters. The weight of 110.4 oz / 3.13 kilograms (without magazine and optics) is distributed over a total length of 35.5” /  901 mm. The telescopic stock can, as the name implies, be adjusted in length. Tele-Fold is the name of this furniture part and it can be locked in five positions. The butt stock features a 0.4” / 1 cm rubber recoil pad. In addition, the stock can also be side-folded, so that the Virtus can also be comfortably sling-carried – see images.

Upper and Lower receiver are held together by two takedown pins. The joints are solid and the view of the trigger unit showed the usual AR-15 minimalism, but in the Virtus it’s first-class quality without even the hint of machining traces. On the lower receiver there are also the ambidextrous safety, the magazine release, the pistol grip with a cap showing the company logo, which hides a inner storage compartment.

The upper impresses just as positively as the lower. The continuous Picatinny rail with the removable flip-up sights is factory standard. Also included is the M-LOK fore-end and the flash hider. The fore-end also features strongly rounded corners. Thus, the Virtus can be grasped with and without gloves - even if everything feels a bit rough due to the coating. If you do not like this handguard, there are plenty of other options open to you. Gas block and the like are typically AR-15-style. The charging handle can be easily pulled backwards with the middle and index finger. This handle can be removed after tilting up, including the bolt. The locking lugs, as described, feature a more tapered design than is common with other AR-15s. The double springs along with their guide and all other components are without ridges, scatches or other abnormalities. You can really say that lower and upper are of convincing quality. The only question now was how the Virtus would behave on the shooting range.

SIG Sauer MCX Virtus Sport: technical data

Model: MCX Virtus Sport
2349 euro
.223 Remington
110 oz / 3120 g
24.3” to 35.5”  (617 to 901 mm)
Barrel length: 
16.6” / 421 mm
single stage standard
Barrel thickness: 
0.65” / 16.5 mm (diameter)
Twist rate: 
Magazine capacity: 
10 + 1 
lands and grooves
plastic / metal
pivoting lever, firing pin
Charging handle, bolt and plastic cap of the SIG SAUER MCX Virtus Sport.
Charging handle, bolt and plastic cap of the Virtus. No part - even the plastic cap - was criticized by the testers.
Adjustable gas block of a SIG SAUER MCX Virtus Sport.
A view of the adjustable gas block of the Virtus Sport.

With the MCX Virtus on the shooting range

For the test fire, the rifle got back to the SLG Niederweimar shooting range, where it was fired at 100 meters. For the optics, we used the Romeo4 and Juliet4 from SIG Sauer. Five types of ammunition went through the rifle. Generally speaking, it can be said that the gun is easily controllable when firing. The Virtus trigger breaks at just over 5.3 lb / 2.4 kg. Norma secured the day's victory with its 56 gr bullet and a grouping diameter of 32 mm. In the following places, the RWS Target Elite Plus (77 gr; 35 mm) and the Hornady ammo (55 gr; 36 mm). It must be noted that some cycling problems occurred with the winning load. Inquiries at SIG Sauer revealed that this was a plastic bullet problem. AR-15s tend to be a bit fickle when it comes to shooting plastic-tipped bullets - and that's exactly what Norma ammunition is. The other types were swallowed by the rifle without any issue - and shooting became synonymous with joy .

SIG Sauer MCX Virtus Sport: our wrap-up

 SIG SAUER MCX Virtus from right, with loaded magazine outside the gun and ammunition in .223 Remington.
Sporty and even more: different magazines are available for the MCX Virtus.

Apart from the fact that the testers might have wanted a riflescope, the test went off as expected. Qualitatively there is nothing to complain about the Virtus – not for nothing is it already used worldwide. Results were satisfactory with this combination. Even if the name of Virtus ends with "Sport", it does not mean that this is its only intended use. For hunting, these "black rifles" do not enjoy a particularly good reputation, but they are also suited for this use. Weight and technology combine in this rifle to a good overall concept, which can also be used for hunting with dedicated optics. And that's where the MCX Virtus comes in, since its long version is also suited for hunters. The only negative point in this context is the caliber: the .223 Remington is only suitable for a limited game range. With an AR-10 in .308 Winchester things would certainly be better.

However, SIG Sauer plans to offer this gun in .300 AAC Blackout – but this is not clear yet. At the request of many hunters who would like to use a suppressor, SIG Sauer has already reacted bringing a 5.56mm taper cap / suppressor adapter on the market . This allows for the mounting of a silencer (where allowed by law, of course) on the MCX Virtus in caliber .223 Remington. The MRSP for the adapter is 12 euro and it is already available in stores.

Further information is available on the website of  SIG Sauer USA .

Another inexpensive AR-15 from SIG Sauer is the M400 TREAD .

All4shooters.com also took a look at the new pistol models from the SIG Sauer Mastershop .

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