Practical test: CZ 600 MDT Grey bolt-action rifle in .308 Winchester – Can it keep the 0.75 MOA promise?

Strictly speaking, the history of the CZ 600 began almost half a century ago when the former Brno company (since 1990: Česká zbrjovka, CZ) introduced the bolt-action CZ ZKK 600. Equipped with a Mauser action, available in various calibers and with a wide range of features, this rifle type developed into a hunting rifle classic. When the Czech company introduced a new bolt-action rifle series in 2021, it was given the name CZ 600 as a tribute. The series included the Range, Alpha, Lux, Ergo and Trail versions (see here our article) until the CZ 600 MDT Grey and CZ 600 MDT Deep Bronze versions were added at the SHOT Show and IWA in 2024. Both are available in 6mm Creedmoor and .308 Winchester; the latter is the standard caliber. "MDT" stands for Modular Driven Technologies, a manufacturer from Chilliwack in the Canadian province of British Columbia. The company is one of the world market leaders in the field of chassis stock systems. The CZ designers equipped each of these 600 models with an aluminum chassis from this manufacturer. We ordered a CZ 600 MDT Grey in .308 from the CZ wholesaler AKAH in order to get to the bottom of it technically and test it extensively. This also involved the question of whether the test gun could deliver the precision of 0.75 MOA at 100 metres guaranteed by CZ.

Barrel, buttstock and chassis center section of the CZ 600 MDT Grey

The barrel is produced by cold hammer forging and has a right-handed M18x1 muzzle thread, behind which the diameter increases from 22 mm to 27 mm at the rear. It is nice to see that CZ provides the barrel root with information on caliber, twist rate and muzzle thread. On the inside, four grooves take over the bullet rotation, the twist rate of the 24-inch (610 mm) long barrel is 1:10 inches (1:254 mm). Three fixing screws clamp the barrel in the action frame front, which is slotted on the underside. The chassis comes from the same source as that of the CZ 457 MDT rimfire rifle (we tested it here). More precisely: the CZ 600 MDT comes in two chassis types. These differ primarily in the buttstock. The 600 MDT Deep Bronze has one of the MDT type Skeleton Rifle Stock (SRS), while the tested 600 MDT Grey has a chassis that the manufacturer MDT calls "Composite Carbine Stock" (CCS). "Composite" refers to polymer on the buttsrock and aluminum in the action area and handguard. "Carbine" in turn reveals that the buttstock is mounted on the center section of the chassis using an AR-15-style buffer tube.

The length of pull of the fairly simple CCS buttstock can be varied using spacers. Four spacers are included in the scope of delivery and change the stock length by a quarter of an inch, or around 6.3 mm. This results in a distance between the trigger blade and the butt plate (length of pull, LOP) of 330 to 355 mm. The two screws on the butt plate must be loosened to remove/attach the spacers. The cheekpiece height, on the other hand, can be adjusted without tools. The cheekpiece can be moved up or down by 36 mm by loosening two brass clamping screws. When the cheekpiece is fully lowered, however, the two screws are fiddly to operate. However, they are clamped tight enough so that the jaw has neither axial nor radial play in the set position.

The MDT Elite pistol grip sits on the center section of the chassis, tilted backwards by 20 degrees from the vertical and very easy to grip. (On the 600 MDT Deep Bronze, the pistol grip is vertical.) The safety lever is located above the grip. It can be operated from both sides, which is easy even when wearing gloves. The magazine release can also be reached from both sides. When pressed, the magazine drops freely out of the well, which fulfils a military requirement and helps with dynamic PRS shooting under time pressure. The 205-g MDT sheet steel magazine holds 10 cartridges, designed for a maximum total cartridge length (L6) of around 73.5 mm. There is a "Barrier Stop" at the front of the magazine well. If you want to mount a bipod, you can do so via a 310-mm long Arca Swiss Rail at the bottom of the handguard. There are also seven M-LOK mounting points at 3, 6 and 9 o'clock. The recoil lug at the connection between the action and chassis is fitted into the chassis body. The underside of the action therefore has the corresponding groove. The chassis has a grey Cerakote coating, which gives the CZ 600 MDT Grey model variant its name. Accordingly, the Cerakote coating on the CZ 600 MDT Deep Bronze is bronze-colored.

CZ 600 MDT: action, bolt and trigger

The steel bolt features 6 lugs in 2 rows. To remove it, slide the polymer disassembly tool supplied over the bolt and then turn it clockwise by about an eighth of a turn. This unlocks the bolt so that it can be pulled backwards out of the chamber tube. If you now push the ejector about 3 to 4 mm towards the bolt face, the bolt head is released. It can be removed in a T-slot guide at right angles to the bolt tube. The bolt head is designed for a "controlled feed", as known from the 98 action. The lower lug is precisely angled to guide the rim of the cartridge. Advantage: when feeding from the magazine, the cartridge is pushed up into an open breech and thus held in place. The extractor therefore does not have to be pressed into the extractor groove of the case, instead this groove slides directly into the claw from below. As a result, the cartridge cannot fall out of the ejection port when it is fed into the chamber, even if the rifle is held in a twisted position. These are gun positions that can occur during dynamic PRS shooting or hunting.

In this case, the ejector does not protrude from the bolt face in the traditional sense. Here it is controlled. This means that it is positioned towards the base of the bolt face and therefore does not have to be pressed in against the spring force when feeding and locking the chamber. The fired case therefore does not automatically fly out when the bolt is opened as soon as the case mouth passes the front edge of the ejection port. The case is guided axially and straight to the rear. The ejector is only activated and extended by the abutment of the bolt catch when the bolt has completely overrun the magazine. This is the "cartridge overtravel". It can be felt by a slight resistance on the last three to four millimetres of the bolt travel. This has advantages. Firstly, the case is only released and flies out when the bolt is fully open. This pleases the reloader. He can either remove the cartridge case by hand beforehand or eject it gently. This is useful for hunting, as the fired case is only released when the bolt head is behind the cartridge base of the top cartridge in the magazine. With conventional models, it is technically possible for the case to be ejected before the bolt has reached the overtravel. In this case, no new cartridge is fed, which can be critical in some hunting situations. Disadvantage of the overtravel: for a proper case ejection, the bolt must be pulled with momentum against the bolt catch, otherwise the case will remain above the magazine. The locking element of the bolt catch is located at 6 o'clock in the action and therefore runs in the axial groove of the chamber. However, the operating part of the bolt catch is located at 3 o'clock on the right.

A 175-mm Picatinny rail with no pre-tilt is mounted on the steel action. It is locked in place by a fitted bushing in the receiver. The slotted underside of the receiver in the barrel mount area reveals that the barrel of the CZ 600 can be changed. However, the three clamping screws are secured with threadlocker and the screw head is also coated with sealing wax. Therefore, only a gunsmith should change the barrel. The pull of the direct trigger can be adjusted with a small Allen key supplied by turning the corresponding small screw by 90 degrees. A total of four settings (6.5 - 9 - 11.5 - 14 N) are available, each with a tolerance of +/- 1 N according to the factory and marked with corresponding dots.

Practical test of the CZ 600 MDT Grey with GPO Spextra 6x 4.5-27x50i riflescope – RWS Target Elite Plus with best accuracy

More and more manufacturers are advertising sporting bolt-action rifles with precision guarantees, especially if these firearms fall into the PSR or Long Range category. From a marketing point of view, this is a good thing, as the potential buyer is guaranteed a minimum level of accuracy, which suggests that the gun has been manufactured in a reliable process. For example, CZ also quotes a shooting performance of less than one MOA (= minute of angle, 29 mm at 100 metres) with three rounds of match-grade factory ammunition for 600-series variants such as Alpha, American and Ergo. For the 600 Range and the two MDT variants, the company even promises 0.75 MOA (22 mm at 100 metres) with five rounds of match-grade factory ammunition.

In order to test this promise as objectively as possible, the testers fired 14 sport factory cartridges and 6 handloads over the relevant sporting distances of 100 and 300 metres. The CZ was also fitted with a suitable riflescope: a GPO Spectra 6x 4.5-27x50i with illuminated PLRi reticle and 34-mm main tube. Underneath was a block mount without a pre-tilt. As usual, two to three dozen cartridges first went through the rifle so that the barrel could bed in a little and any burrs could be rubbed off – at the muzzle, for example. This also allowed the testers to familiarise themselves with the gun. The first 30 test shots were spread over 6 groups of 5 shots each. It was noticeable that the accuracy improved significantly as the number of shots increased, even though the test loads were the same. This shooting phase was therefore extended to 50 cartridges. The last trio of 5-shot groupings (= shot numbers 36 to 50) then showed almost identical values. This means that the barrel went through a so-called "break-in" period, i.e. the firing load after which accuracy stabilises at a certain level.

After the 50 shots, the barrel was cleaned with Addinol W18 gun oil and a bronze brush. Of the 14 factory cartridges, a total of 10 remained below one minute of angle over a distance of 100 meters and 6 fell below the value of less than 0.75 MOA specified by CZ. The rifle delivered the best accuracy with the heavy bullets (190 grs) of the RWS Target Elite Plus: 10 mm or 0.34 MOA. Sub-MOA accuracy was achieved with all 6 handloads tested, 5 were 22 mm or better, i.e. below 0.75 MOA. For precision reasons, the testers did not shoot from the magazine, but loaded the cartridges individually. This was as smooth as it was trouble-free due to the very smooth action. Admittedly, two aspects were a little unfamiliar at first: the different resistance just before locking and the controlled ejector pin, which requires a complete travel of the bolt to eject. Firing from the sheet steel magazine filled with 10 cartridges also went without a hitch.

CZ 600 MDT Grey technical specifications and price

Test results for the CZ 600 MDT Grey

The gun is excellently finished, all controls are easy to reach, adjustments set on the stock remain in position. The case ejector takes some getting used to, but it also offers advantages. Otherwise, the only thing that bothered us was that the clamping screws for adjusting the lower part of the cheekpiece were difficult to reach. With a proud 11 out of 20 test loads, the CZ 600 MDT achieved the specified shooting performance, i.e. 22 mm or better at 100 meters. In short: for just under €3,000, the prospective buyer receives a versatile bolt-action rifle in the familiar high CZ quality.

More information on CZ firearms can be found on the CZ website.