MAC Takes A Look Inside The Kel-Tec RDB

George Kellgren is certainly one of the most inventive small arms designers alive today, although his company Kel-Tec has unfortunately become known for their QC troubles and availability problems more than how inspired the designs are. The latest offering from Kel-Tec is no less inventive than previous designs; it is an intermediate-caliber bullpup designed to eject brass downwards, away from the shooter’s face, while being as simple as possible. The way this is done is perhaps better seen than read, so below is embedded a video of Tim from the Military Arms Channel taking a first look at this unique rifle:

The first thing of note is the rifle’s unusual fire control group. A long hammer mounted at the very rear of the receiver allows rounds to pass through the gun’s downward facing ejection port during ejection, while still giving clearance for the hammer to build sufficient momentum to strike the round’s primer. The bolt group is a simple seven-lug Stoner-Johnson-esque unit (though derived vs. the AR-15; it uses a different profile) with the extractor located at the 6 o’clock position, and two ejectors to give the cartridges the requisite velocity to make it out of the chute at the rear of the receiver. The bolt carrier uses a simple fixed oprod connecting it to a short stroke piston of some variety, probably a short, fast-moving tappet similar to an AUG or FN SCAR.


A promotional photo showing the RDB’s mechanism. Note the hammer and spring connector bar, in yellow. Image source:

At the risk of editorializing somewhat, the RDB’s design is one of the most well-though-out bullpups to be released in years, in this author’s opinion. This isn’t to say the rifle is the “end all be all bullpup”, but rather that its basic mechanism is the work of careful creative thought that elegantly solves the problem of ambidexterity in bullpup designs without adding excess weight and cost. There are a couple of potential problem areas, however. The first is the exposed operating rod, which reciprocates visibly over the front handguard housing. This is a very lightweight arrangement, but depending on the details of its construction could potentially cause problems when debris makes it way into that area, if it interferes with the oprod’s cycle. However, that area may also be clear enough for it to not be a problem, only testing will tell. Kel-Tec has also used a magazine release design similar to that of the IWI Tavor – which in the Israeli rifle is reportedly sensitive to accidental release.

2015-10-19 01_37_36-New Kel-Tec RDB Bullpup - YouTube

The RDB field strips fairly simply, though unconventionally even by bullpup standards.

Does the RDB offer enough improvement to finally allow bullpups to make major inroads in the tactical rifle market? It’s difficult to know, but the RDB’s unique and simple mechanism certainly provides a good foundation for a solid product.

Nathaniel F

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He is also the author of the original web serial Heartblood, which is being updated and edited regularly. He can be reached via email at


  • Dracon1201

    Looks like something I will have to but to compliment the KSG.

  • thedonn007

    Yea, I watched the video earlier today. Not sure if I want to sell my Tavor yet.

    • Laserbait

      Why sell the Tavor? Have both!

  • TDog

    Kel-Tec is like Lucy from The Peanuts… yeah, they say we’ll kick that football, but just you wait…

    I am not a fan of taking promises to the bank or worse yet, paying for them.

  • Vitsaus

    After the AUG, the Tavor has more or less settled the bullpup debate in military use. Every month you will run across an article with some group or another adopting it. I don’t think Kel Tec has the QC nor the availability of sufficient materials to ever produce a weapon suitable for military use.

    • Giolli Joker

      Tactical market is not military use. ?

  • Don Ward

    Good write-up. I can’t help but think that every Kel-Tec design is gimmicky and looks like something Homer Simpson designed.

  • Edeco

    George Kellgren: The John M Browning of the 21st century! Sorry not sorry.

  • TexianPatriot

    Keltec marketing program…
    1. Make one prototype.
    2. Put out pictures and tell everyone how cool and innovative it is.
    3. Make 5 more.
    4. Sell those 5 while thousands of others are on waiting lists.
    5. Design a new gun and forget about building the latter.

    • Zang Kang King


    • Rock or Something

      You forgot:

      6. PROFIT?!?

      • supergun

        The keltec 380 sucks. The folding 9mm is pretty close. The 22 mag. is ok but not worth $450. The shotgun looks interesting, but I will take the Mossberg 930 SPX tactical.

    • supergun

      Thats funny.

    • Smootchie

      Not this time… i picked one up for a seemingly reasonable price and initial impressions.. KelTec did their homework on this Bullpup, I prefer it to my AUG and the Tavors I have fired. It remains to be seen hopw durable this RDB is but so far it seems robustly built.

  • kregano

    If they actually make a lot of them, and maybe toss in a spare .300 Blackout barrel, I’d buy one.

    That said, that exposed rail that the mag release runs in and the inability to check the chamber are kind of worrisome.

  • hking

    LOL @ the “military” guy in the ACUs using it. They have to be delusional to even have the thought that any military would field a Kel-Tec system. These things belong at the range or in someones safe, that’s about it.

  • DetroitMan

    Kellgren has some great ideas. His company needs to get better at marketing and quality control. In addition to that, none of his designs are really hardened for military service. I think he could be a competitor in service rifle designs, but his design approach and Keltec’s practices suggest he isn’t interested. He may end up being the next Melvin Johnson: some of his ideas incorporated by others into firearm designs that are more successful than his own.

  • Jeff Heeszel

    The problem with the gun is it covers up his meticulously-groomed beard.

  • Vhyrus

    If it comes in under $1000 street price they might have something. As it currently stands I cannot imagine trading my Tavor for one. The ejection is a non issue. I have had many right handed people fire my left handed Tavor and none of them even mentioned the ejection port position. The apparent lack of a bolt release also kills it for me.

  • A.WChuck

    Kellgren runs KelTec as a hobby. There is no real concern on his part about being one of the “big guys”.

    • eisenjj

      Too late, they’re already the third largest U.S. manufacturer of firearms based on 2014 sales.

      • Dan

        How is that even possible? All I hear is how it is impossible to find a keltec anything anywhere?

        • Edeco

          I don’t know about the 2014 sales as such, but the 32’s and 380’s seem to be readily available…

          • Zang Kang King

            And that’s just it, THESE and lots of. They work too.

          • davidio flavio

            Junk is what the picture show. I owned three all failed to fire with dead trigger systems.

            When will I buy another Krap Tech product?


        • Laserbait

          You can’t find them because the sell so quickly. The shelf life for any KelTec at my dealer is about 1.5 days.

          • A.WChuck

            My dealer (biggest in Florida) claims they can rarely get anything other than the pistols and the occasional KSG.
            I really wish KelTec would license more designs.

  • JK

    I’m definitely buying one. Looks great! I agree the company needs to keep up with production.

  • WH Morgan

    I’d love to get my hands on one, but why, oh why in the wide wide world of sports do they insist on those “uncaptured” takedown pins. It was the main thing I disliked about the SU-16 (and the reason I got rid of mine), and they’re doing it again with this one.

    • Dan

      Maybe the production guns will have captive pins? I would hope anyway.

    • Phil Elliott

      Simple work around on my Su16, drilled and tapped the pin, added a piece of nylon covered cable to it and screwed it to the stock. Ouila, captive pin.

      • iksnilol

        No reason to get rid of a gun due to such a small flaw. Easier and better to just fix it like you did.

  • Smokey_the_Bear

    it looks like a winner, I know I want it. But it all boils down to when & how much…?

  • Wolfgar

    The design looks good from a picture perspective. The stock doesn’t look too long and has good human engineering. The gas system looks like a long stroke piston, not a short stroke. The bolt carrier looks small compared to others which should reduce recoil, Captive pins would have been a better choice. Back up sights would have been another nice addition. Over all it looks like a better execution than the ill fated MSAR Aug clone. Looking forward to more reviews, as this rifle may be a future addition to my family.

  • Slim934

    Damnit Janet. That is a brilliant little design. Even if they do not produce very many of them…..Dat concept.

    Even if keltec doesn’t go anywhere with it, at some point somebody will mass produce the crap out of that.

  • Cal.Bar

    Gee, I want a bullpup… I can get a battle tested bullpup designed AND USED by one of the finest armies in the world… or….. a Keltec. Used by…. well no one. Tested by…. no army. Sure – I’m in. And while you’re at it, please make sure it throws the hot brass down the front of my shirt on my feet so that when I have to move after shooting, there will be a pile of hot slippery brass at my feet to help me on my way. I’ll stick with my Tavor.

    • Dan

      Bro, the hot brass melts to your soles, giving them tactical grip. Um just not on hard surfaces. Also what if I am mall ninja enough to wear a vest of some sort that has pouches near the ejection port? As in blocking it.

      • wetcorps


      • Beju

        Ideal for arctic operations though, it’ll be like having studded tires.

    • Vitor Roma

      The Tavor fart in your face if you supress it, and in case you are lefty, it is a whole ordeal to change ejection side. Also don’t forget with an awful trigger, for the pleasure and profit of Geissele.

      • HSR47

        Gas to face can be an issue even without a can: If you shoot it fast enough, the gas venting from the gas block will blow right in your face.

    • anon

      >stop making new things because i like my thing

      You realize that people like you are why we had the dark ages?

  • Edeco

    I’m noticing a lot of comments about their output. Of course it’s frustrating. I’d point out though, since they’re anything but a bolt-action-rifle/double-barrel-shotgun type company, Kel-Tec are lightningrods for proposed regulations. As such, I don’t blame them for limiting their expansion to what they can do without loans.

    To put it another way:

  • Laserbait

    I’m getting one, possibly two. They’ll have a nice warm spot next to my RFB’s and Sub2K, and get the carp shout out of it like the others do.

  • Lars Thorsen

    Any chance of an ambidextrous loaded chamber indicator? You know- for safety?

  • Uniform223

    The downward ejection system seems pretty cool. Much more simplistic than FN’s P90. I would only worry about debris getting into that area though. Either way if Kel Tec would truly develop this. IMO it would be one of the best if not THEE best bullpup out there. That being said I wouldn’t mind spending the money… again if they develop it properly.×1280.jpg

    • Vitor Roma

      Are you worried about anti-gravity debris?

    • iksnilol

      I thought P90 also ejected downwards?

      • Martin Grønsdal

        Uniform said keltec’s downwards ejecting system is more simple than the p90. In other words, both guns have it 🙂

      • Uniform223

        The magazine for the P90 is located on the top

        the magazine its self seems too complex for what should be the simplest part of the firearm (IMO)

        The rounds must be rotated into position via the magazine to line up with the chamber. Because the magazine is on top, the round naturally exit out the bottom. KelTec’s RDB’s ejection method seems more simplistic and it takes AR-15 mags.

        • iksnilol

          The mag is pretty simple, just a ramp that the round slides down while turning 90 degrees in.

          It is less fast to load tho.

  • TJbrena

    After seeing this, they probably decided to redesign the entire rifle around the bottom-ejecting system, adding years to the process of getting it to market.

  • Pete Sheppard

    I want to see how a chamber check is done, as well as malfunction procedures

  • AD

    I don’t like the mag release; looks too easy to hit by accident. Other than that I think this looks really, really good. I’d love to see a 308 version, not sure if that’s feasible or if the stock would need to be too long.