Czech M14: The ZK-420S Battle Rifle at James D Julia

The ZK-420S is an experimental Czech rifle that is virtually unknown today, but which was remarkably influential, bearing significant elements of the Garand and several other Czech designs, and influencing the M14 and Kalashnikov rifles. Originally designed by Josef Koucky in 1942, the plans were hurriedly dusted off and improved at the end of World War 2. With many nations looking at the possibility of adopted self-loading military rifles, Brno hoped to make export sales of the design.

The ZK420S uses the trigger mechanism of the M1 Garand and a gas operated rotating bolt action very similar to the Garand and AK rifles. It has a simple adjustable 3-position gas system, and a quick and simple disassembly procedure. It uses detachable box magazines (10 round, and not copied from an existing design) and was made in a variety of calibers for testing – including 8×57, 7×57, 7.5 Swiss, 6.5 Swedish, and .30-06. Examples were trialed or examined in the United States, Argentina, Israel, Ethiopia, England, Switzerland, Sweden, Norway, Denmark, and elsewhere – this particular rifle is from the Norwegian trials.

In my opinion, it is an excellent rifle, and its failure to sell was probably due to price and the combination of tight budgets and cheap surplus war material in the late 1940s. It is handy, well balanced, and has a good magazine design and good sights. Recoil is comparable to the Garand. Ultimately the development program in Czechoslovakia would lead to the ZK-472 in 7.5x49mm, which would proceed to the 7.62x45mm in the vz.52 rifle.


  1. Thanks for showing this unusual rifle. Actually, for me this is the first time I am able to see it inside. In time prospective, this had been created and tested in very short time period (if I omit the fact it was secretly worked on during occupation), which was apparently limiting factor for its greater popularity.

    The label under “Zbroyovka Brno” (‘arsenal’ – written phonetically)says “narodni podnik”. Those 2 words mean “national enterprise”. In fact in one of first moves the National-socialist (nothing to do with German Nazi party) party government of pres. Benesh after liberation in 1945 did was that it declared widespread nationalization of industries (I believe in first wave it was all key industries and all with number of employees at 200 and more). This was some 2 years before communist takeover. So again, this is testimony that all this offering and testing abroad happened in very short amount of time.

    On technical side it is true that the trigger mechanism is of M1 variety; even later vz.52 caries on with same. If I was to compare those two I’d say that this is a lot better design (I own vz.52 and studied it into detail) and quite frankly wish to know, what was Koucky brothers role in vz.52 and why they proceeded that way. As far as deemed influence of previous designs or being influential later, I believe this is just coincidence and subject of speculations. Speculations are good, they are fun 🙂

    • It’s very good to know that the Czech weapons were only nominally in line with demands from Moscow for standardization. After all, it’s not like Czech soldiers would be conscripted to fight in Afghanistan during the last years of the Cold War. I could be wrong, but still, one can imagine that other satellite countries kept domestic arms only for national defense unless the higher-ups permitted exports (strictly for national interest deals, not for profit). Did I mess up?

      • “After all, it’s not like Czech soldiers would be conscripted to fight in Afghanistan ….”
        Yeah, right, they are being conscripted now. Mind you, not at ‘conscripts’, but as “professionals”. How you tell the difference? By beard; we had to be clean shaved.

        Sorry, I could not have this one go unnoticed. 🙂

      • For practical reasons it is better to use fewer weapons system (replacement parts supply for example). Notice that Czechoslovakia used not only own hand weapons but also bigger weapons for example see Samohybný protiletadlový dvojkanón vz. 53/59 „Ještěrka“ which was 30mm AA gun (caliber not used in Soviet Union at that time)

        • Daweo, just a couple of memories I read here and there. Btw., there are some good history-technical pages like and you may want to look at.

          Czechs were always thru those ‘fateful’ years (With Soviet Union Forever and Never Otherwise) prone to do funny kicks. As I recall they developed anti-tank gun which was just as good as it gets. In comparison test in Union, it was visibly superior. The Russian gun was by those who saw it “jumping like a goat”. Was it adopted? Yeah, you guessed it.

        • That 30mm gun you mentioned was originally intended for Kriegsmarine – submarine defense. After war they brushed it up and doubled.

          Last time I saw it in action (including its motor-carriage) was in Croatian “war of independence”.

          • “Last time I saw it in action (including its motor-carriage) was in Croatian “war of independence”.”
            Query in English wikipedia states that 110 were delivered to Libya, so it is possible that it is still in usage, I don’t know any photo evidence but I am not expert at contemporary conflicts in Maghreb area.

  2. “In my opinion, it is an excellent rifle, and its failure to sell was probably due to price and the combination of tight budgets and cheap surplus war material in the late 1940s.”
    I would say that political history has also influence. Compare it to Belgian SAFN-49 which got commercial success and was sold to Third* World countries.
    Belgium was obviously on other side of Iron Curtain.
    * – in 1950s sense, all countries not aligned with NATO and not aligned with COMBLOC

    • Hey Daweo, where you have some Russian equivalent (or better)?
      🙂 It looks I have ‘day of chuckle’ today.

      As you can see, the forced adherence of CSR to comblock screwed-up chances of that country on every front. And no, I do not blame anyone for that; believe me.

      • “(…)some Russian equivalent (or better)(…)”
        So far I know there was not active development of full-power cartridge self-loading rifle between end of WW2 and 1958 when competition for new sniper self-loading rifle started (and finally lead to SVD being adopted in 1963).
        Soviet Union had big storage of SVT rifles which can be used in case of emergency; closest equivalent which was in production was probably SKS with disclaimer that it fired weaker cartridge.

    • Well, Daweo, the SAFN-49 was only a mitigated success. It was born, or better said, produced a bit too late, when large quantities of surplused WWII rifles could be had for much smaller price tags. Also, much better battle rifles were becoming available by then, including FN’s own FAL.

      • There seems to have been a bit of quality control trouble as well. For instance, the Egyptian contract SAFNs in 7.9 x 57 had a reputation for going full-auto due to sear nose breakage. It sounds as though there may have been some heat-treatment issues there.



  3. “cheap surplus war material in the late 1940s”
    Obviously there was cheap surplus in 1940s, but so far I know self-loading rifles were rarer (thus harder to get) that bolt-action repeating rifle (see how Madsen model 1947 rifle fared) or sub-machine guns (see Madsen m/45 or SIG MP 48). If someone decided to align with United States then probably could obtain M1 Garand, but if decided to align with no-one?

    • M1 Garands were given away by the crate load to anyone that wanted them, so a decent self-loading rifle was not hard to procure by a prospective nation’s military.

      I would be prepared to pay well for a remake of this rifle. I’ve never warmed to the M1 or M14/M1A, and the ZK-420S seems like a very solid and well thought out rifle.

  4. I wonder with the advances in investment casting and improved cnc technology if this would now be a viaable and marketable rifle like the Ruger Mini-14 and the M1A/M14 series. Especially with the options of intermediate cartridges now available. It looks like it could make a excellent sportsman rifle

  5. Ah, yet another rifle we could have seen quite a few of floating around if it succeeded.

    It also certainly looks like both a refined M1 and a finer M14.
    I also noticed in the high speed footage from the movement of the charging handle that the bolt carrier didn’t smack into the heel of the receiver. Is there a particular reason that more rifles didn’t do anything like that? Too much work getting the spring to be the right strength to prevent the impact without causing it to not strip a cartridge when you could just stick a buffer in there or beef up the impact zone like with the M1?

  6. A shame this design did not have more exposure. Ian is correct in that is a wonderfully handy rifle firing a full power cartridge. I love the FN-49’s but compared to the ZK, they are chunky and ungraceful. You could almost transistion the ZK into a hunting rifle with no modifications, they look that well designed. Ah, the road not taken…..

    • You would be required to eliminate the bayonet lug and keep the magazine capacity at ten rounds or less to convince the completely stupid anti-gun people that the ZK-420 isn’t intended for serial killing.

  7. You keep saying that the trigger is a copy of the garland. Have you considered that the garland trigger is a direct copy of the mg 13?

  8. For those interested, Ceska Zbrojovka is pronounced kes-kah zbro-jove-kah
    the Z isnt silent but its not fully pronounced either, the best way to explain it is like this.
    The z indicates that you should start the letter B with your mouth ready to say sh like in “she” and all you need is a slight “hiss” before the B but it is not a separate syllable.

  9. What a fantastic rifle, and totally unknown to me.

    Since M1A rifles sell for $1,500, could a modern made 420S sell for a profit at $2,000? If using modern CNC manufacturing techniques, I don’t see why not.

    Because of its (arguably) mixed heritage, the 420S might appeal to many different kinds of rifle fans in America, from Garand groupies to Kalashnikov kooks.

  10. Well, I’ve seen and touched one of these rifles some 44 years ago.
    On the receiver is a “Národní podnik” mark, which means “nationalized company”, a form of ownership that, as far as I can tell, was not known until 1945. Maybe I am wrong and that form of socialized ownership exited before? Someone with more insight in Czechoslovak history?
    Still, the Czechoslovak communist coup d’état was not happening until February 1948, so it is a good question as how much the upcoming communism had to do with the commercial failure of this gun. The communists perspectives were rather bleak until the actual coup.

    • I somehow overlooked your question and since so far there is no one to react, so I will jump in with my second class knowledge.

      The inter-war CSR was officially “free-enterprise, democratic” based state. However, in reality, life conditions for 3/4 of population were not good. That gave rise to strong Communist party founded in 1921. This coupled with Western betrayal in Munich had led in 1945 to sharp rise in Com-party popularity to point that they earned in 1946 gen. elections 36% of vote. That said however may not overshadow the fact that Csl. government in exile (London) was, especially in second half of the war, pursuing balanced policy of co-operation with both the West and Soviet Union. It paid off only to some degree until communist coup-d’état in Feb. of 1948.

      What happened shortly afterwards and what followed some 8-10 years after was not the same thing. While the foolish and extremist policies after February of 1948 did not produce much good and led to general disillusion, the ruling Kom. party was gradually changing direction and was fostering more broadly oriented trade. Thus it happened that many products of Csl. industry (and if was not by far just arms) started to penetrate world markets and gain recognition.

      • What you said about the foreign trade of Czechoslovak manufactured goods (in the 1950s) is quite true: despite the general availability, to those who could pay for, of both Italian and Spanish-made Olivetti typewriters in Spain back then, a oncle of mine got a Czech-made compact typewriter back then. Such machines had a solid reputation.

    • I do not want to go into undue length of citation of past events, but what is important to count in as a factor of changes in internal policies of the country, was death of Stalin in 1953. After arrival of Khrushchov in USSR, the so called “cult of personality” (e.i Stalin’s dictatorship) was revealed and publicly pilloried. That had a substantial and positive effect on public life and economy in CSR. I’d venture to say, that by this very process the ‘edge of communism’ was dulled to great extent. After that there was no chance to return to old and nasty policies, although the com. lead government kept looking after many aspects of social life in order to make sure that reigns of power stayed in its hands. This state was drastically altered by events of 1968, albeit just temporarily.

      • I think I solved the issue that bothered me: the “Národní podnik” mark comes after Benes’ decrees of October 1946 when the Czechoslovak industry, the arms industry and Z. Brno included, was nationalized. I seem to recall that the 420S model was produced in 1946 only, but I don’t remember where I’ve read that.
        Denny, thanks; somehow, when I’ve your answers my memory cogs start rotating.

        • Very good, you are welcome!
          Benes was man of compromise, at least he tried. Commies let him die naturally, as a favour.

  11. Ian, will you be doing a video on the first model FG-42 coming up for auction at Julia this month? That would be a fantastic piece to look at in depth mechanically, historically and perhaps could even be compared one on one with the second model that Julia has in the same auction. Seems like too great an opportunity to pass up (unless the owners/consigners won’t let you access it, which would be unfortunate).

  12. Now little about “surplus material” on showcased rifle. Frankly, in Czech industry, there has not been such thing.

    For those who are not familiar with Czech steel making industry in city of Kladno, known as Czech Manchester I just say that much; they are there since 1898 and are one of top producers of high quality steel. Their product was used on Carcano rifles and during WW2 on crankshafts for German fighter planes. It would be stretch to think that Czechs did not have quality steel right in May of 1945.

    While some other plants such as Skoda in Plzen were heavily bombed by Allied air-force, Poldi Kladno escaped largely unscathed. After many changes in ownership and down-scaling in 1990s they are back in business and hiring staff.

      • Yeah, Ruy… that’s what I gather.

        Some of one time large enterprises almost disappeared and then they emerged in someone else’s hands and in fractional size. Poldi is part of one big German steelmaking outfit. Another one I know quite intimately – this being Aero, is still making planes, currently in co-operation with Embraer.

  13. Ian,
    Have you noticed on every slow motion film of a rifle firing there is significant carrier bounce ? Do you think that the cam track could be altered on the M16 for instance to stop it ?

    • Carrier bounce may be indication of part of energy is not absorbed into frame/ buffer. It is often a demonstration of system elasticity, which is higher end of the game and by the way rather intriguing one. I’d say, better bounce than not; that is on buffer’s end of stroke. On front end it would be bad news and if that is what you mean, it may be point of contention.

      Comparison with M16 camming does not bode well with this design. One reason is obvious – direct gas impulse duration as opposed to energy stored into operating rod. On M16 length of cam is 0.31″ (8mm); on this is some 0.8″(20mm) – my estimate. If that is the case, there is not much wrong with controlled bounce. But yes, I also wish to see the slow motion video, for sure. Let’s hope Ian will be able to return to it, before rifle is sold.

  14. I remember seeing this rifle in a book perhaps 25 years ago, one crappy little black and white pic, and I was hooked…THIS is as beautiful looking and technically impressive rifle, and if I were a wealthy man, there would have been a SERIOUS bidding war between the victor and I…

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