NEW Piston 5.56/300BLK – Sig Sauer MCX Virtus

Sig Sauer has just released an update to their popular MCX platform. Branded the Virtus, Sig is debuting three of the four new models, leaving one cloaked in secrecy for the time being. Available as a Carbine, Short Barreled Rifle or a Pistol with Brace, the new gun shares many similarities with its predecessor.

After browsing the images and watching the videos, it appears that the adjustable gas block and trigger may have seen some design updates whereas the remainder of the changes are mainly cosmetic. The Virtus does feature a folding, five position stock and fully ambidextrous controls.

At $2,335, the MSRP seems on the high side for a  heavily saturated and discounted market. However, I’ve been wrong before and I will be wrong again – let’s see where the retail price settles before making any predictions. Check out the details below.


Sig Sauer Virtus SPECS:

  • CALIBER – 5.56 NATO / 300 Blk
  • MAG TYPE – AR-15
  • MSRP: ~$2,300


Conceived for the demands of the Special Operations community, the MCX VIRTUS Patrol from SIG SAUER is engineered for adaptability, accuracy and longevity. Cold hammer-forged 16” barrels are user-changeable and available in 5.56 NATO and 300 BLK, offering the utmost in mission-specific flexibility. SIG’s proven internal recoil system offers reduced recoil and a compact platform. To enhance accuracy, the MCX VIRTUS features the new Matchlite™ Duo trigger for crisp, clean feel. Free-floating M-LOK handguards are available in four lengths. Ambidextrous, AR-style controls and a folding and adjustable stock enable the MCX VIRTUS Patrol to be tailored to any shooter. Available in Stealth Gray and FDE and built with the highest-quality components that enable it to go 20,000 rounds without part replacement, the MCX VIRTUS is the apex predator of the carbine world.

The yet to be released model:

Sig Sauer – Facebook


LE – Science – OSINT.
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  • USMC03Vet

    Would rather see a AK pattern rifle from one of the big companies. The market is definitely there if they product something of quality. The AK market in the US is in dire times right now and ripe for some hero to swoop on in producing quality AK models.

    • Xtorin O’hern

      sig just needs to start making proper 550 series rifles again, enough with these meh mutations of the AR-15 and they they get back to what was good.

      • Whatever

        Or bring them in as pistols, like someone else is doing.

        • Xtorin O’hern

          wait… a company is doing that???

          • john huscio

            John doe industries out of texas.

          • Rob

            John Doe Investigations

      • noob

        or have IMI do a budget galil variant, with all the dust covers and top rail done well.

    • feetpiece _

      Sig tried and failed with the 556R/xi.

      • Haulin’ Oats

        Yes, but those are not the same quality of 550’s they still make and sell in Europe and in a time long long ago, were exported to America.

        • john huscio

          Sig sauer won’t import them because they don’t want competition for their own rifles.

        • No one

          Which are still a quite flawed design and massively overpriced for what you actually get.

          • Rob

            Expensive? Absolutely. Flawed? Not really. They function fine and are durable. They do not bring any tangible benefits over a quality AR despite the price increase but that does not make them flawed.

          • int19h

            What exactly is flawed about the original SIG 550?

      • Duro Sig

        I still enjoy my sig 556r (version 2). I wish they still produced them. excellenbnt platform to build off of.

      • 360_AD

        Yes and no. Where Sig went wrong with the 556R:
        – They didn’t make sure it was GTG right off the bat, instead letting retail customers be the beta testers (angry ones)
        – Instead of admitting to lack of development and testing, they blamed it on customers using steel cased ammo. Who in their right mind would release a rifle chambered as the AK is and not fire steel cased ammo??
        – Due to backlash they eventually got it right with Gen 2. Mine functions flawlessly and is more accurate out-of-the-box than any AK I’ve owned including Arsenal/Izhmash

        Even though they fixed it with with Gen 2, it still:
        – Suffers from perceived bad build quality and engineering. A $1200 rifle should not have a sloppy fitting handguard
        – Has a charging handle that could fly off during firing (though not personally experienced)
        – Not a stamped steel lower like the original 550 series
        – Too little too late to fix damaged reputation

    • Ebby123

      The only appeal AKs had to the general market was price. Once you get out of the $350-$600 price range, the mainstream sales value of a “high-end” AK all but disappears.

      Its a design that’s every bit as antiquated as the AR15, but with a much smaller feature set, almost no modularity, and (consequently) much less aftermarket support.

      • Max Glazer

        Whats “modularity”? Ability to swap uppers with a different barrel? It’s a problem that never existed until some marketing genious suggested it. Easier to simply take another rifle when you need it and not worry about taking your rifle apart and swapping parts over. And you won’t see SF or infantry carry spare uppers.

        Ability to hang accessories on it? Plenty of railed fore-arms, siderail adaptors, stocks and pistol grips. WHich also refers to “aftermarket support”.

        AK is a platform that is even more proven then AR-15, in right hands it’s every bit as capable as AR-15 and also happens to exist in 5.56.

        • Justin Clark

          Define capable. How many precision rifles are made off of the AK platform? Because just about every single model currently under production is patterned using one or more components of Stoner’s design. It is now and always has been an apples vs. oranges argument with the use of an intermediate cartridge being really the only similarity; two COMPLETELY different ways of going about the same thing. And they can both accomplish it pretty efficiently.
          It seems like it is against the rules of the firearm community to admit that something can be just as capable as its counterpart on the battlefield while remaining inferior at the same time. I’m sure that if you wanted to pay $10,000 for an AK, you could eventually get sub-MOA accuracy out of a 6 pound rifle. But that can be achieved in an AR platform for about 10% of that cost. My point is that from the factory, a production AK will ALWAYS be heavier and less accurate albeit generally more durable than its production AR counterpart.

          I want to stress that I have 2 AKs and I love them. But this argument is silly. One weapon was developed with the resorces and ingenuity of the strongest economic power the world has ever seen and the other was developed by a country with no economy to speak of. Why don’t we ever hear about how much better the Tokarev is than the 1911? It’s the exact same argument. I like 7-11s coffee just fine, but if it’s my money I’m going to Dunkin Donuts.

          • Max Glazer

            If one WANTS to, one will make an AK with a machined receiver, a match barrel and a stock that’ll be level with the barrel. Make a light-weight bolt carrier and reduce the gas pressure in the gas system. Voila! Here is your precision AK. ANYTHING is possible. But then you are turning an assault rifle into a sniper weapon.

            M-16 was developed with all that “resorces and ingenuity of the strongest economic power the world has ever seen” and the combination it came out as, proved to be a piece of excrement that soldiers tossed away when they had a chance and grabbed the weapon that was made by “country with no economy to speak of”. When will people finally realize that for a good weapon to be made one doesn’t need massive corporation with billions of dollars or to be in a huge economy? One needs BRAINS.

            Again that bull about accuracy. Russians had tested AK-74M against M-4 that they got from Georgia and it turned out that in full auto it was more controllable and with tighter groups. Single fire group was only marginally bigger at all combat ranges. Soldier will make more difference then the gun. Rob Ski had been hitting targets out to 500 yards with AK in a 7.62×39 and videos are on youtube. So your argument about “inaccuracy” of AK is nothing but load of excrement.

            AK is heavier for that exact reason of required durability. Which also happens to allow the weapon to have milder recoil since heavier receiver absorbs shock of the impact of bolt carrier better then if it was lighter.

          • noob

            anybody tried full auto accuracy trials on an AR-pattern carbine firing 5.45×39? the AR’s inline internal piston DI system plus the lower recoiling cartridge that used to be the province of the AK74 might produce even tighter full auto groups…

          • Max Glazer

            I’m unaware of any AR pattern rifles that fire full auto which are chambered in 5.45×39. The conicity of the rounds would require a proprietary magazine, a different magwell (or lack of it) and a different feed ramp profile to think of just a few alterations needed to produce such rifle.

  • Gun Fu Guru

    Anybody know why the SBR is longer than the pistol w/ brace?

    • Rob

      The SBR pictured is the 5.56 while the Pistol is 300blk. The SBR and Pistol have identical barrel lengths in like calibers.

    • Ebby123

      If I had to guess – the arm brace is more compact. I think the SBR version is measured with the stock fully extended.

      • Gun Fu Guru

        The upper is longer if you count the MLOK sections.

        • Rob

          Different calibers have different barrel lengths. If you go to the Sig web page you will see both lengths pictured for the pistol and the SBR.

  • Miguel Sanchez

    Looks like the version that the London CT-SFO are using except M-lok instead of Keymod. Still a bit out of place in todays market though, shame. it does seem like an interesting platform, just so damn expensive when AR’s are dirt cheap.

    • FarmerB

      I have one of those models of MCX. They are quite a handy platform, a bit pricey for the build quality, but at least no buffer tube. Interested in a better trigger, M-Lok and adjustable gas block.

    • Rob

      London CT-SFO are using the original MCX with the telescopic stock and 11in barrel that has been on the US Market. This new model has a few changes including a heavier barrel, new handguards(the top rail of the receiver is shorter meaning they are not backwards compatible), heavier profile upper receiver, two stage trigger, new finish, improved charging handle and stock(now shipping with the legacy rifles as well). Despite the over the top marketing this seems like a step forward for the MCX and should represent what the rifle should have been at launch.

  • Raptor Fred

    M-LOK and an adjustable gas block. Hopefully that 308 MCX is gonna be made now.

    • James Young

      Guessing that’s what the “Model yet to be revealed” is

      • Rob

        While I would like to believe that, the “final chapter” appears under the Virtus. That leads me to believe that it is a variation of said series of guns. My guess is that it is a gun packaged with a silencer beneath the hand guard like the honey badger or Sig’s own LVAW, potentially perm attached to the barrel. If you go to the Sig Sauer homepage you will see a clip of a similar gun in their Virtus banner.

        • noob

          hmm – are they still able to do that huge muzzle brake that can be the baffle stack of a suppressor if you add a cylindrical tube of metal around it or did that get struck down in court?

  • jonp

    I’m sure it’s awesome. Just not $2,300 awesome. Who are they marketing this to? I could buy 2 each 5.56 and 300blk for that money

    • Ebby123

      Retail is about 65% of MSRP for a lot of SIG products. That’ll put it around $1,500 at the counter.

  • HSR47

    The marketing BS in that video went WAY too far.

  • Kelly Jackson

    The problem is you’ll never be able to sell guns like the Sig 556 as long as the arm chair operator crowd is screeching you can buy an AR15 for $399.

    Non AR15 rifles are expensive, $1,200 – $2,000 expensive, and that’s just the way it is.

    • Ebby123

      Standard AR-15s have become the new Glock.
      It does most of what people need it to do, its reliable, and cheap.

      To get an increase in features or performance via a non-AR15 platform, and the cost goes up significantly.
      Also with modularity / aftermarket support being a key benefit of the AR-15, you can close that gap even further with some modification.

      That’s why for me, if I’m going to depart from the standard AR pattern platform, it will need to be for a compelling advantage the AR system can’t provide me with – like a bullpup 308 (IE Tavor 7).

    • 360_AD

      Huh? Armchair operator would not be vouching for the $399 AR. They’d be singing the gospels of LWRC, Daniel Defense, Noveske and any other overly hyped high dollar AR (which could cost well over $2k). It’s the guys who aren’t and know that a $399 AR could work just as well.

  • Sasquatch
    • Rob

      I never understood why people compare the market price of one item with the MSRP of another. There is 102.00 dollars separating the Legacy MCX and the Virtus at MSRP. That means that there will be less than that separating the dealer price between that and the MCX. The finish along would account more than account for the increase.

    • Ebby123

      Looking at previous SIG MCX products, you can expect retail to be about 35% below MSRP. The MCX Vitrus will be selling for around $1,500 retail.
      Still expensive, but that puts it on-par with most mid to “high end” AR-15s on the market right now.

      (Example: The MCX Patrol MSRP is $2,131, but you can Buy-it-Now on gunbroker for $1,400.)

      • Sasquatch

        Of that is the price of your “mid range ar” you got jacked.

  • RazorHawk

    They should have removed the stupid forward assist. I love the user changeable barrels though, makes cleaning so much easier.

  • Mel

    So Knowing SIG this wont share any parts with the original sig MCX any current owners will be SOL on parts.

    • Jack

      Heck, you still can’t get parts for the MCX. And what little common parts it shared with the AR, like bolts was done away with when they had their idiotic recall. I bought and MCX. And sold it.

  • Ebby123

    SIG’s retail prices are ussually shockingly below their MSRP for some reason.
    I would expect this to land around $1,400 retail.

    • Ebby123

      EDIT: probably closer to $1,500 or $1,550.

  • john huscio

    So this is why buds is blowing out mcxs at 1300 bucks….

  • john huscio

    Did alot of research between the MCX and the 516 and i think I’ll go with the 516 for my next purchase….with sig’s aptitude for discontinuing rifles, who knows how long the virtus/mcx platform will be around…….the 516 at least has some pretty decent LE/military contracts to anchor it in their lineup.

  • David Goldberg

    “This is actually the perfect rifle…”

    Where can I mount my bayonet?

    • mig1nc

      M-Lok mounted lightsaber.

  • int19h

    One thing that this definitely proves is that everything does look better if you replace Keymod with M-Lok.

  • Chris R.

    When will this be available for purchase?

  • Lance Blinent

    Looks like the MCX found its way to the discontinued section on their product list