B5 Systems

Live Fire – USSOCOM Suppressed Upper Receiver Group (SURG)


I recently had the opportunity to fire the newly selected USSOCOM Suppressed Upper Receiver Group (SURG), built by SIG SAUER. It’s based on an MCX upper receiver group and is designed specifically to work with the suppressor attached. The suppressor is considered integral to the design. However, the direct thread suppressor is removable by the operator, for cleaning and maintenance. The weapon is also capable of firing without the suppressor, however there is no muzzle device. In that case, there is a gas selector, which will most often be used to deal with ammunition issues.


For the units receiving SURG, they’ll mate it to their issue M4A1 carbine lowers, giving them access to the MCX piston driven upper.


Here’s a video of me firing SURG in fully automatic mode. The upper is paired with a SIG full-auto M400 lower receiver due to availability at SIG Academy. You’ll also notice the adapter knuckle which allows the MCX upper to fit on an AR lower. Don’t take anything away from my smiling demeanor, I always look like that. And yes, it is front heavy; every firearm equipped with a suppressor shares this trait.

Although it’s not the intent, even after several magazines, the suppressor shroud could still be touched with the barehand. All the same, I don’t recommend you do this at home. Lots of variables are going to influence how hot the barrel, suppressor and shroud become and how quickly.


Instead, what this does demonstrate is that the shroud will mitigate injury and damage to equipment caused by a hot suppressor. It’s success is a combination of design and materials. There’s plenty of room for the heat to dissipate, and the Aramid cord wrap resists melting or sticking to other surfaces.


Due to SOCOM concerns, SIG is still being tight lipped about performance data, but it had to meet some very stringent selection criteria, which I went over when the upper was selected in August.


Once the SOCOM contract is fulfilled, SIG plans to offer SURG for commercial sale. However, don’t expect it to come cheap.


39 Responses to “Live Fire – USSOCOM Suppressed Upper Receiver Group (SURG)”

  1. Dave says:

    Hopefully in before the Sig haters who find any reason to bash Sig and their ability to win contracts as of late.

    • Stefan S. says:

      Funny we’re buying weapons from a country when the last time they sent troops into battle, Michelangelo was painting a ceiling!

      • Stefan S. says:

        Oops my bad they were bought by a German company in 1976.

        • MA says:

          Sig Sauer USA is totally US owned. The Germans sold it for virtually nothing to the US entity nearly 20 years ago.

          • Lukas says:


            In January 1985, SIG Sauer established a subsidiary, SIGARMS, in Tyson’s Corner, Virginia, to import the P220 and P230 models into the US. Two years later the firm moved to a larger facility in Herndon, Virginia and introduced models P225, P226, and P228.

            SIGARMS moved to Exeter, New Hampshire, in 1990 where production facilities had been established and production began on the P229 in 1992.

            SIGARMS and its European sister companies were bought by Michael Lüke and Thomas Ortmeier (L & O Holding, Germany) in October 2000. In 2007 SIGARMS changed its name to SIG Sauer Inc.

  2. Joe_K says:

    This is why I follow SSD, great stuff! The suppressor shroud reminds me of a certain commercially available handguard for AR type firearms.

  3. b_rawrd says:

    Interesting wrap, I see someone’s GI Bill degree in basketweaving has finally paid off.

  4. Airborne_Fister says:

    Idk if it was just the video but that is one quiet firearm!!!

    • Kyle Kata says:

      It is the video.

      Their 556 can is quieter than a Surefire at the ear, but… still not hearing safe on that short a barrel.

      But… The amount of gas coming off that (almost none) was pretty damn impressive for being indoors. It’s clear the really worked that gas system be to suppressed. Looks good.

  5. Thomasjane says:

    Is there any info about the quantity of these to be purchased or basis of issue? I saw that it’s a IDIQ contract- does that mean it could be anywhere from zero to tens of thousands?

  6. MTW says:

    I know this has been brought up in previous SURG threads on this site, but I am curious to see how end users navigate the compatibility of additional items such as lights/lasers with the large OD suppressor. I’m curious to see if users have issues with floods on PEQ’s /MAWL’s etc.. over the can. Or if we will start seeing “offset” style mounts for lights and lasers that place them further from the hand guard.

    • John says:

      I was wondering that too.

      I wonder if guys will just remove the shrouds when they get downrange.

      • SVGC says:

        John I was thinking the same thing. It looks like the shroud is removable via those 4 screws. Though the shroud was part of the whole point, if it’s removable I wouldn’t be surprised in the least to see more than a few sitting in pelican cases.

  7. Jack says:

    12 comments and no mention of the single most essential item in this video.
    I was silently cursing at you for displaying cutting edge unobtainium earpros that you probably didn’t even really need at that point… *kick rocks*

  8. Hubb says:

    That is an interesting way that Sig attached the burn guard to the suppressor. The Larue Tactical SUURG attaches the burn guard to the handguard.

  9. kemp says:

    pardon my ignorance but what exactly does this do that a mk18 with a surefire can doesn’t?

    • SSD says:

      Considering that combination wasn’t submitted for SURG, we don’t know. But USASOC units won’t get this. They’ll use SureFire suppressors with their currently issued uppers, just like they have been.

    • Dave says:

      Designed to run suppressed, so theoretically should have less gas in the face of the shooter. MK18s are full Simple Jack on gas. Also this allows for a folding stock, which is nice for certain things like exiting automobiles. MLOC is nice too.

    • Rob says:

      This has better OTB performance than the MK18, which is likely important to the units that will get them. Plus the folding stock and the fact that it was designed to work together with the suppressor from inception as well. The burn guard can help when working in tight environment or vehicles as well.

  10. Dennis says:

    Did you ask Sig if they would offer a similar suppressor shroud for their other standalone suppressors or if Sig would offer a similar suppressor shroud and suppressor combo without the other components of the SURG?

    • SSD says:

      There are no plans to do that. The shroud is very expensive. They don’t see the juice being worth the squeeze.

  11. Zetavu says:

    But the URGI Geiselle what happened to it? Had not he been chosen by USSOCOM?

  12. RC1701 says:

    I see others have asked about USASOC, NAVSOC, etc., but what about JSOC? Are they going to replace their HK416s with these? Would the HK lower work with a SIG upper the as easily as SIG’s own designs or a mil-spec M4 lower?

  13. RC1701 says:

    Joint Special Operations Command, the component that overseas Delta and DEVGRU. I was curious because they use the HK416, which already has the gas piston system the SURG uses. If they are adopting SURG, that’d mean they’d basically be paying however many thousands of dollars per rifle for just the fancy suppressor, which seems like a bit of a waste of money to me. Upgrading SOCOM M4A1s by giving them the gas piston and better suppressor makes sense, but if you already have piston-driven rifles (like the HK) surely it’d be a waste of money? They’ve already got the better heat dissipation of the piston system, and from there they can just fit a SureFire suppressor with a heat dissipating cover, effectively creating a less expensive, homemade SURG.