Sig MPX Submachine Guns

Who doesn’t love a sub-gun? Blasting through cases of cheap pistol ammo is my favorite way of turning money into noise, and I imagine with the new Sig MPX series that amount of fun would be amplified.

The MPX is an extremely compact, magazine fed, selective fire SMG that fires from a closed bolt, and is extremely suppressor friendly (which seems to be the selling point). Of course the MPX has been spotted before in the hands of Sig employees and at shows like SHOT, but I figured I would give my impressions of the weapon system.

First, the MPX comes in two flavors: Regular and kurz. Both are very lightweight and I could see myself competing quite well in a sub-gun match with them. Here is the larger gun with a suppressor installed:


For those familiar with the AR platform, you will feel right at home on the MPX. The charging handle, mag release, bolt catch, and selector are all right where they should be. Also the stock is quite sturdy considering it is a wire design.

As for the kurz model, everything is the same, but shorter as the name implies:


While short, it isn’t MP5k short. Here is me with each gun so you can see how more or less each sizes up:



My smiles always look so forced.

Each gun was insanely light, and I would say the suppressed full size MPX is as light as a 9mm UMP (if not a tad lighter).

Now usually mini and micro SMGs compromise shootability for compactness. While the MPX Kurz is no exception, I did find it easier to point and manipulate than an MP5k PDW with a castle rear sight and clumsy stock/foregrip:


I will do whatever it takes to get a demo-letter for a post dealer sample, as they are just too damn cool!

For information about the civilian legal MPX, click here!

Alex C.

Alex is a Senior Writer for The Firearm Blog and Director of TFBTV.


  • JumpIf NotZero

    Funny thing… I’ve own an MP5 SBR and OWNED an MP5-K SBR… I’ll tell anyone flat out, the shorter 5″ SBRs are not nearly as nice to shoot. Suppressed or not I always preferred my MP5 to my MP5-K and TP9. I get the appeal of the the K, I do, it looks awesome in movies.

    Ugh, what I wouldn’t have given for SIG to make this take MP5 mags!

    Oh, also…. Those stocks SUCK for actual shooting. Again, look really cool, sort of suck though. I have an A2 and A3 for MP5s and the A3 is never used when shooting. I’d be wary of anyone buying this without really getting a handle on it, as the rail slots are built into the gun, it’s clearly designed to use this stock.

    • Man, I am right there with you on your MP5 preference!

      • KestrelBike

        Alex, what is your take on the wire stock (A3) for shooting? Do you think they’re completely uncomfortable like JumpIf does?

        • They definitely are not as comfy as a full stock, but the bars are wide so they are not like mac 10 bad or anything.

          • raven

            The MP5SD I shot last year was one of the softest shooting full autos I’ve ever had the privilege to get behind. I also shot several other pistol caliber full autos including a 9mm full size UZI with it’s steel stock and although not as quite as soft as the MP5, it’s recoil was almost non-existent. I don’t see what the fuss is about with the MP5 wire stocks, the gun shoots so soft it’s really not noticeable.

          • I agree. Plus stocks are easy to swap out. Punch out a pin, remove existing stock, attach new stock, push pin back in.
            It is funny to think that when the MP5 came out, it was the pinnacle of modularity, haha.

  • Davidio Flavio

    WHO Cares! It’s not like us regular, lowly citizens can can ever own one.

    As far as I can see its a preview of what can be used against us……

    • I care: I appreciate all kinds of firearm technology, and can appreciate things I can’t own or afford. Hell, I can’t own a Ferrari F430, but damn if I don’t like them!

    • Jeff Smith

      Immediately after this artle was published, another article was published stating that Sig Sauer would be releasing civilian versions of this exact firearm.

      Here’s a delicious plate of crow – enjoy!

  • Davidio Flavio

    Oh. Probably not kosher to get demo letters just to enhance a collection.

    I heard the ATF has been scrutinizing these as of late.

    • Of course, I will demo it to an interested PD!

  • Cymond

    “extremely compact, magazine fed, selective fire SMG that fires from a closed bolt, and is extremely suppressor friendly (which seems to be the selling point)”

    You seem to have forgotten “gas operated and rotating/locked bolt”. Blowback 9mm carbines are known for having a choppy recoil feel. A locked breech and gas operation should smooth things out.

    • Yep, gas operated w/ rotating bolt.

      That said, I have shot just about every blowback SMG under the sun and I would not describe the recoil as choppy.

  • Lance

    Another MP-5 knock off of sorts. Just wish they make MP-5s for civis again.

    • Paladin

      They do, you just can’t get them. Germany has some rather strict export laws coupled with the US’s import laws means it’s not happening any time soon. H und K actually does make a couple models of the MP5 for civilian sales within Germany.

    • José Pulido

      Firing 9mmLuger, having a wire stock, and being short are not things that make guns knockoffs of the MP5.

      An MP5’s only advantages over this would be nostalgia, and track record(and cheaper production because of stampings, and possibly because of pre-existing tooling, but considering it’s H&K, not necessarily cheaper price tag unless it’s a licensee maybe.)

      Undeniable advantages over the MP5(for Americans at least):
      Button mag release.
      Bolt lock/release.
      AR-15 pattern controls.
      Picatinny rail that should keep the weapon lighter/smaller over the various ways optics are mounted to MP5s.

      There are other advantages, such as having more hand space without having to worry about a charging handle, having a cleaner operating mechanism(which will wear out more slowly than the roller delayed blowback, but those are more matters of opinion.

      • Mp5s have button mag releases (and paddles), some models have bolt catches, there are rails and even keymods for them now, rails can be welded to the top, and you have a non reciprocating therefore non interfering charging handle. Delayed blowback guns have numerous advantages in pistol calibers over gas operated designs. I assume you do not have much SMG trigger time?

  • gunslinger

    cheap pistol ammo?

    also, almost looks like neo from the lobby scene of the first matrix.

    • Wheel weights = free bullets.

  • inglwud

    Too “expensive” that’s why I own a hi point carbine!

  • Mazryonh

    Did the SIG guys tell you why they didn’t go with a design that loaded from the pistol grip, like the Beretta Mx4 Storm? Loading from the pistol grip gives you a better barrel-length-to-overall-length ratio, and is more intuitive to load.

    I hope one of the authors here on this blog gets some range time with the Mx4 Storm soon.