The CZ 1012 is a tremendous semi-automatic line of shotguns that use a gas-less inertia operating system. That means instead of redirecting gas from the barrel to cycle the action, the 1012 uses a spring within the bolt to store energy during the shotgun’s recoil. This stored energy is then used to rotate and unlock the twin lugs from the barrel extension and extract and eject the spent shell. A spring then drives the bolt forward to chamber a new shell and lock the bolt into the battery. 

The system’s major advantages are that it requires less overall cleaning and maintenance, reduces felt recoil and allows the shotgun to reliably cycle a wider variety of ammo than most gas guns can, without adjustment. 

Taking a 1012 Apart and Putting It Back Together

The first thing that should be noted is a CZ 1012 shotgun with a synthetic stock has a slightly different assembly/disassembly process compared to a 1012 with a wood stock—but the overall process is quite simple. 

CZ 1012 Assembly Process – Synthetic Stock 

The 1012 must be assembled and disassembled with the bolt in the locked-open position.

1. Simply place the synthetic forend over the lug on the bottom of the shotgun barrel attached to the mag tube.
2. Slide the barrel assembly together with the receiver, guiding the magazine tube through the opening in the forend.
3. Once the two major assemblies click in place, finish by threading the magazine tube cap onto the front of the mag tube.
4. Perform a function check, including the manual safety, to make sure the assembly was completed correctly.

CZ 1012 Assembly Process – Wood Stock 

When attaching the wood forend, instead of simply placing it over the lug, keep the wood forend angled up and slide the front of it over the lug on the bottom of the barrel from the rear. The rest of the forend can then be lowered into place.

After that, the process is the same as that of the synthetic stock models. 

To disassemble, simply reverse the process. First, remove the magazine tube cap. Then, slide the barrel out of the receiver. Once the two halves are separated, the forend can be removed. A synthetic forend can be lifted straight off the barrel. To remove the wood forend, tilt the back of the forend up, and then pull it off the lug on the barrel. 

An Important Reassembly Note

The bolt of a CZ 1012 must be locked open for disassembly and reassembly. If the bolt is somehow released while the gun is disassembled and is no longer in the locked-open position, you will not be able to assemble the shotgun, and you will notice that the bolt cannot simply be pulled back. 

When the CZ 1012 ships, a block is placed in the action to prevent the bolt from moving forward. It would be wise to keep this block on hand so the gun can be disassembled for transport or storage without any concern. 

However, if the bolt should move forward unintentionally while the gun is broken down, there’s an easy fix. You will need a thin implement that won’t mar the gun’s surface—a long wooden cotton swab will do; the magazine restriction plug that comes with the gun or even a thin brass cleaning rod. Use it to maneuver the strut that prevents the bolt from being retracted out of the way from the side of the action while pulling the bolt back. The bolt will lock open, allowing you to assemble the firearm as normal.