XS 24/7 Big Dot Tritium Express Set Night Sights Installation and First Impressions:


    Those of you who watch TFBTV may know that I am a concealed carry instructor and a daily carrier. Although I tend to switch rigs often based upon the circumstances, I generally favor a Glock 43. (See James’ Top 5 CCW Picks here). The 43 is Glock’s single stack 9mm pistol that is rugged, reliable, compact, and shares many similar features and handling characteristics with its larger relatives like the Glock 19 and Glock 17.  (See a review of the Glock 43 here).


    With this in mind, XS sent me a set of the 24/7 “Big Dot” tritium night sights to install and evaluate on my Glock 43. I consider myself to be ham-fisted and only capable of basic gunsmithing tasks – I think AR lower assembly is the furthest extent of my skills –  so I confess that I was somewhat anxious about the prospect of installing a set of sights on my daily carry gun.

    My worries marginally subsided when I received the package:


    It looks like there’s a full set of tools for installation in here, an instruction manual, and reference to a video walkthrough:

    Many of the tools you need are included.

    Many of the tools you need are included.

    I got all my gear out – Glock, laptop, sight set, newspaper and microfiber towel to prevent self-inflicted spousal homicide, pink rubber duck that I forgot to remove from the shot.

    Ready to punch (the old sights out) and screw (the new sights in).

    Ready to punch (the old sights out) and screw (the new sights in).


    Red thread locker is included.

    Red thread locker is included.

    Also, it’s pretty easy to get into; no rage-wrap here, just a plastic case fastened with two staples.

    Easier to get into than a senior citizen's bank account (it doesn't require selling a convincing mortgage scam.)

    Easy access.

    The instructions say you “need” (manspeak for “suggest”) pliers, a file, a hammer, alcohol, and q-tips. As you will see, I used only the hammer (in addition to the provided tools).


    You might ask “what are Walrus Gunsmith Tips?” I would not have known either had I not also checked XS’s video walkthrough and been greeted with this masterpiece of a ‘stache in XS’s video walkthroughs.

    There's a tutorial on XS's site about installing the Big Dots and maybe a PSA about diabetus.

    There’s a tutorial on XS’s site about installing the Big Dots and maybe a PSA about diabetus.

    And that bears mentioning: XS has excellent tutorials on its website for the installation of its products. I know many of us have been unable to wrap our heads around a manual from time to time,  maybe trying to figure out exactly what direction that non-descript, curved arrow is moving on the two dimensional paper in front of you. Video gives a good audio-visual instruction as well as a representation of three dimensional space, making the process easier to figure out.

    Not that I needed it.

    As it turned out, installing the XS sights was one of the easiest mods I have ever undertaken on my Glock. It lasted all of about 15 minutes.

    The instructions tell you to clean off the sights and the contact points on the slide with q-tips and alcohol. I omitted this step because I don’t have any alcohol in my house that I can’t drink. Next, you use the provided mini-hex wrench to unscrew the front post. Again, very easy.



    Add a little thread locker to the base of the site, the screw, and the site threads, and then do the same thing you just did, but in reverse. In what may have been the only “tricky” part of the entire installation, you need to be mindful of the sight being properly aligned with the barrel – i.e., straight. There’s a little play in the XS front post in that it wobbles a little side to side, but you should be able to line it up well enough by eyeing it.

    Next, remove the rear sight. This is of course a task made monumentally easier with a sight-pusher, but I decided to do it the “hard” way to see how difficult the “hard” way really was. I used a regular hammer (not included) and the non-marring sight punch. I got it started by laying the slide on its side on a towel and giving the rear sight punch a few knocks with a plain claw hammer. That got it started, and I used (quite a bit of) finger pressure to get the sight the rest of the way out.


    The XS sight slides easily into place and locks into the dovetail with a couple of small set screws. XS suggests that you generously apply thread locker to the contact points and the set screws before and during the installation of the rear sight.

    P1230041 P1230043 P1230042

    All in all, this was a very quick and easy installation, taking under 15 minutes for a first-timer. This is an excellent way to add a tritium front and rear sight to your Glock 43.

    As far as my first impressions of the XS set go: I am very familiar with the XS sights from my days working in a gun store, when numerous SIG P245s would come in equipped with the big dot. I was never impressed. To me, the slim, solitary sliver of a rear sight marker combined with the giant front dot represented imprecision: In my opinion, it would quicker but more calculated to align a front sight blade between a symmetrical rear pattern, and it would be more precise to use a smaller front sight that would not completely occlude the intended target.


    As far as the rear sight goes, you can’t ignore the inverted pyramid shape of the gutter that forms the top of the sight: during the day, this certainly functions in an instinctive manner, perhaps even easier to use than the more geometric half box sight that comes on the Glock 43 from the factory.  Relatedly, the front sight seems to be geared towards expediting the sight picture/sight alignment phase of firing a defensive shot; at least in theory, it would appear that getting that dot on the target in close quarters and aligned in the gutter and above the rear sight line might be quicker, even if less precise than the standard 3 dot. And after all, closer distance is much more forgiving of aim, but much less forgiving of delay, so maybe XS has its heart in the right place with these sights.

    And while it seems like the XS sights are built for speed rather than exacting accuracy, there is at least some anecdotal evidence out there that the XS can eke out ten-ring shots in the hands of a capable practitioner, or with a combo of a large front/rear set: Massad Ayoob had this to say about the XS Big Dots:

    For very fast, close shooting another worthy option is the XS “express” sight, a humongous big globe over a very shallow “V”-shaped rear sight with a central line in the middle. I’ve seen some folks who can make that work very well for accuracy at distance, and at least two of my students have placed “top shot in class” with XS sights over the years. I have the XS Big Dot on my favorite backup gun, the J-frame S&W Model 340 M&P revolver, largely because the front sight is mated in that model alone with a proportionally large square rear sight. It allows head-shot accuracy at 25 yards which I for one can’t achieve with the “lollipop sight picture” of the XS rear sight, but is just as fast as the “express” style in close. Best of both worlds.


    I haven’t had a chance to take these sights to the range, but when I do, I’ll update this article with a comment. In the meantime, any of you Big Dot sight users out there: I welcome you to sound off in the comments and tell me about your experience with the 24/7 Big Dots.

    James Reeves

    • NRA-licensed concealed weapons instructor, 2012-present
    Maxim Magazine’s MAXIMum Warrior, 2011
    • TFBTV Executive Producer
    • Former Regional Sales Rep, Interstate Arms Corp., MA
    • Champion, Key West Cinco De Mayo Taco Eating Competition
    • GLOCK® Certified Pistol Operator, 2017-2022
    • Lawyer
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