Tactical Tailor

Proof Mark – Muzzle Stand-off Device for the Glock 19 & 23

Proof Mark LLC is a veteran owned firearm accessories design and manufacturing company located in the Pacific Northwest. They recently released their Muzzle Stand-off Device (MSD) for the G19/23. Project development began in October of 2015 and concluded in Spring of 2018.


The design intent originates in part with the Battle of Qala-i-Jangi where an SFOD-A, after expending their ammunition, had to defend their position using their empty weapons in hand-to-hand combat.  Another source of inspiration was a special mission group in Slovakia, where there were several reports of Glock slides coming out of battery due to muzzle contact.  The MSD has utility in kinetic operations and as well as CCW. FBI statistics show more than half of law enforcement firefights take place at distances of 0 to 5 feet.  When in close contact with an assailant the MSD prevents the slide from being pushing out of battery.

The MSD body is machined from billet 7075 aluminum and the glass break is 17-4 stainless.


The locking mechanism consists of a Patent Pending 303 stainless locking block which fits within the profile of the STANAG 4694 rail and allows for tool-less removal.


The MSD went through extensive testing which revealed two primary design obstacles; gas management at the muzzle and frame fitment.  First, capturing excess gas behind the stand-off device generates a tremendous amount of force on the pistol dust cover and this can lead to material fatigue.  This challenge was overcome with the use of proper venting.  Second, inconsistencies of Glock dust covers between generations and even within a single generation made universal fitment difficult.  To overcome this obstacle, balance was struck between critical dimensions to achieve a good fit on Gen3/4/5.

With solutions engineered and production eminent, Glock released their new Gen5.  This extended the development cycle as the slides of the Gen5/19X are longer than prior generations which caused interference with the back of the MSD.  This was overcome by recontouring the back of the MSD.

Prior to public release, the MSD went through a year of testing within one of the military’s special mission groups with positive feedback.

The MSD G19/23 fits the Safariland 7TS G17/22 XC1 holster.  Look for the following first eight digits: 7378-8322-XXX.  The last three digits indicate right/left hand configuration.



Variants of the MSD for the G17/22 and G34/35 are forthcoming.

The company website is: www.proofmarkllc.com.Facebook: www.facebook.com/proofmarkllc

Instagram: @proof_mark


23 Responses to “Proof Mark – Muzzle Stand-off Device for the Glock 19 & 23”

  1. BillC says:

    Or you know, a quality weapon light that extends past the muzzle.

    • tcba_joe says:

      Nailed it.

      • tcba_joe says:

        Wait, I just realized it has a pic rail on the bottom? So you can mount a light that will extend past the device making it utterly useless… *insert laughing emoji*

        • ThatBlueFalcon says:

          As crazy as it sounds, you can still push the slide OOB with a weaponlight mounted. I’ve done it in contact drills, clothing or weapon angles or Murphy all play a part.

  2. reverend says:

    “The design intent originates in part with the Battle of Qala-i-Jangi where an SFOD-A, after expending their ammunition, had to defend their position using their empty weapons in hand-to-hand combat. ”

    Um… not being a dick, but NO ONE carried a KNIFE OR A TOMAHAWK?!? And Empty Glock pistol… Uh….

    • Thomas says:

      Right? I would rather hit people with my Tomahawk then my Glock.

    • SamHill says:

      I also wondered what does it matter if the slide went out of battery, when using your glock as an impact device, if you are completely out of ammo. Sounds like a tough situation and I sure wasn’t there.

      I do know I don’t want to have to buy more holsters though, so expensive!

  3. Horshack says:

    bros! When my TL was in the war in Saudi, he team got over run and had to use there cleaning rods! My ATL wants to t&e one of these for are team for door crashing ops!

    • Dave says:

      My TL must have been assigned to the same unit! He makes us keep a blank taped to our cleaning rods for just such an occasion.

  4. Mark says:

    Honestly, this thing looks cool, but I don’t see any true valued in it.

    If they had somehow worked it to function as a compensator, too, then maybe…but, as is, it appears to actually create more problems then it solves.

    Also, I doubt that there are more than a couple of holsters that will even accommodate this rig, without a weapon light, and probably none for with a weapon light.

  5. pablo says:

    Having to buy new holster/s is a deal killer with these.

  6. willsew4kit says:

    Most bad ass meat tenderizer I have ever seen…

  7. Jonathan Demler says:

    After much man-drama I did watch an Afghan Commando dagger punch the top of some poor ANP officer(?)’s head with a Beretta. This would have been the right tool for that action!

    • ThatBlueFalcon says:

      Afghans swatting each other with AKs was comical… until you realized they were loaded and safety off… to say nothing of the RPG incident!

  8. Stickman says:

    Anyone else old enough (and involved in CQB back then) to remember when these first came out 15 or so years ago? They didn’t sell then, and they certainly are going to have a harder time in the market when an X300 serves as a more functional component.

    Can a light on a slide still make for an out of battery weapon, sure it can, but so can snagging the front sight, ejection port, or a number of other highly improbably things.

    If you are pushing so hard, and canting your wrist so much that your slide is extending past your light, your weapon was going to get limp wristed anyway.

    I’ve personally muzzle punched people in the face and used my pistol as an impact device, and no, I didn’t need this, or the other devices like this which were also recently released.

  9. Todd says:

    Many years ago Al Zita did a stand off device on a 1911 then added a spike to the mainspring, I think Ill stick to a light.

  10. Hubb says:

    Paul Howe and XS Sights figured a lot of this out with the Glass Assault Tool. Check out this website for the different models:

  11. pbr549 says:

    It looks cool though.
    1. Always look cool
    2. Always know where you are3
    3. If you don’t know where you are, at least you look cool.

  12. Brian says:

    I only chime in when I see something as ridicules as this!!! Seriously grab a knife after you throw the gun. A bayonet would make more sense but on a pistol! What are these people smoking???!!!