We all love them, they have a special place in our hearts, we grew up with them and in many cases, we still enjoy them at the range, no matter the age. What are we talking about? CZ 452 bolt action rimfire rifles. Or should I say ZKM rifles? Let’s shed some light on this topic.

CZ 452 STANDARD – May you have one at home perhaps?

Shortly after the end of the second World War Czechoslovak Ministry of Defence requested a brand new training rifle.

The task was accepted by both large-scale firearms manufacturers in former Czechoslovakia. While ČZ Strakonice focused more on the air rifle known as Vz. 47, its main competitor, Zbrojovka Brno (ZB) decided to also focus on a .22 LR caliber.

The fast development, partially based on an existing program started during the Nazi occupation, resulted in three different prototypes by the end of 1945. Normally with such a rapid response from the factory, one would expect the samples to be a bit „rough around the edges“ but in this case, the designers in charge were the Koucký brothers, the legends of our firearms industry being responsible for many successful weapons incl. later bestseller handgun CZ 75.


The prototypes were later called ZKM which is an acronym of „Zbrojovka“ for the factory name,  „Koucký“ and „Malorážka“ – in Czech a general term for rimfire caliber weapons.  Often the rifles were also marketed as Brno Model (or Mod. for short) and 1,2 and 4.

The first one was the basic model „1“, soon supplemented by an improved „model 2“ with a longer barrel (630mm vs. the original 580mm), adjustable rear sight, and a more comfortable stock. The number 3 was omitted for an unknown reason but the variant marked as Mod. 4 or, alternatively as ZKM 456, received a heavy target barrel, a diopter sights but kept all the decent characteristics of the 450 family. Let’s have a look at them now.

Typically for Koucký brothers’ firearms, the rifle is quite simple, very sturdy, reliable, and safe to operate. From the overall perspective the bolt assembly may remind you of a Mauser-style system but in the case of Brno rifles the bolt body itself does not rotate when being unlocked, it only moves horizontally which has a positive impact on feeding reliability. A pair of massive locking lugs present on the bolt handle assembly is used to lock the bolt in place against the matching recesses in the receiver.

Feeding reliability is then even improved by a patented extractor paired with a holder that helps to keep the round appropriately angled and firmly grabbed by the extractor claw.

The trigger is per standard adjustable and its construction along with a safety mechanism makes the gun very safe to use even for novice shooters.

While the concept proved to have huge market potential, the production was rather inconsistent and was finally ceased in the ZB factory at the beginning of the 1960s. That was not, however, the end of the ZKM 450 series of rifles. Quite the contrary actually. It was decided that the production should be moved to the CZ factory in Uherský Brod which had only recently finished a large order of weapons for the Czechoslovak army and had free capacities.

CZ 452 FS – Full-stocked variant

CZ 452 VARMINT – Popular heavy-barreled version took over from ZKM 456/ Brno Mod. 4

The production then continued from 1964 in Uherský Brod under the original name ZKM, later re-named CZ 452 and lasted for decades only being ceased in 2017 when replaced by an improved model CZ 455.

The total production in this factory reached 1.173.727 rifles which increases the odds that this was your first bolt action .22 rifle.

One of the drawbacks of the design, and pretty much the reason why it was replaced by CZ 455 and later CZ 457 was the fact that over the years plenty of variants were made with many dedicated parts for this or that model which was not sustainable. At one point during the production, 35 different receiver options were made at the same time. A nightmare for production planning. The later CZ 455, therefore, changed that and included one particularly interesting option shared by the current CZ 457 as well – barrel interchangeability.

As mentioned already, the ZKM/Brno/CZ 452 story was closed in 2017 with limited editions called „Grand Finale“ and „Farewell Edition“. But thanks to their durability, accuracy and build quality these rifles will definitely stick around for quite a few more decades.