How to fix common problems with BRNO / CZ .22 rifles...

[BrnoB78]

Following an investigation to determine why my vintage ’56 Model 2 BRNO recently began to erratically eject cartridges & spent cases I’ve elected to share some acquired possible solutions for hopefully resolving relatively common problems associated with BRNO / CZ .22 rifles :

If you are not able to regularly eject either cartridges or spent cases then carefully check to see if the leading edge (namely, closest to the barrel) of either the slightly raised ‘old angled / pitched roof’ style ejector lug or the ‘new rectangle’ shaped ejector lug’s visually worn. If so, then replace the easily removed bolt guide / ejector lug assembly which is located below the bolt face when the bolt’s pulled back to its ‘stop’ position. Just remember to buy the identical unit as the uniquely shaped lugs slide into distinctly different angled recessed grooves along the base of the bolt. Note, the earlier angled 'pitched roof' shaped lug was arguably more time consuming and costly to machine, hence the switch to the easier 'rectangular' format on recent versions.

How to remove and replace the bolt guide / ejector lug assembly - simply unscrew the mag housing’s rear retaining screw (it threads into just behind the raised ejector lug) whilst a protruding lip slips into a slot beneath the breech. Remove the bolt and the ejector assembly thereafter slips out towards the butt. Insert the replacement, position the front lip inside the recessed slot, and screw in the mag housing's rear retaining screw - easy.

If the mentioned leading edge of your ejector lug’s fine but you still experience erratic cartridge or spent case ejections then carefully observe the rim’s contact edges of the twin angled claws for sign of obvious wear – replace if necessary. Ensure that you slightly re-tension the claw’s sprung retaining clip (by carefully compressing it between your fingers) prior to re-attaching it. Note, if the clip’s lost some of its power to firmly hold the extractors then, in turn, the case won’t be held tightly enough against the bolt face for it to be kicked free by the ejector.

How to remove and replace the bolt’s twin ‘claws’ - carefully prise open the retaining clip (e.g. with a fine pointed probe) such that the ends just slip over and off the sides of the claws. Carefully note the relative positions of the different shaped claws, then install the new replacement set. Remember to lightly re-tension the retaining clip prior to re-fitting. Note, I hook one end of the clip in its seated position over one of the claws and then use a sharp probe to gently pull the other end into its seated position.

If your mag randomly miss feeds than check to see if the ends of the spring are identically bent / shaped in addition to slightly re-tensioning / stretching the spring. Also, bearing in mind that the follower’s bent end bits might be ‘catching’ on the mag’s inner walls, minutely bend them until miss feeds either occur less frequently or are hopefully eliminated.

Note, simply re-tensioning the twin ‘claws’ sprung retaining clip thankfully resolved my cherished Brno’s ejection problem.

[Camel]

Ahaaaa, now I know who you are. I also post on AHN as Onehump, good that you made it over here mate.

[BrnoB78]

Hi Camel, long time no hear !! Undoubtedly lots of folk similarly contribute to multiple forums. It's arguably all about sharing one's knowledge, experiences and related skills with others.
Cheers.

[Camel]

No dramas mate, it was good that you got the magazine problem sorted, its amazing that such a small discrepence can make so much difference.

[Flip]

Thanks very much for he info, my brothers Brno has erratic ejection as mentioned I shall pass on this

Thanks again

Flip

[BrnoB78]

Flip, I'd recommend your brother to first simply re-tension the the bolt's 'twin' claws retaining clip. In the process, it'll hopefully resolve his erratic ejection issue, as per mine.

[Flip]

Thanks just spoke with him and he is going to try that first as he can't see that the block was all that worn.


Flip

[Gnome]

Following an investigation to determine why my vintage ’56 Model 2 BRNO recently began to erratically eject cartridges & spent cases I’ve elected to share some acquired possible solutions for hopefully resolving relatively common problems associated with BRNO / CZ .22 rifles :

If you are not able to regularly eject either cartridges or spent cases then carefully check to see if the leading edge (namely, closest to the barrel) of either the slightly raised ‘old angled / pitched roof’ style ejector lug or the ‘new rectangle’ shaped ejector lug’s visually worn. If so, then replace the easily removed bolt guide / ejector lug assembly which is located below the bolt face when the bolt’s pulled back to its ‘stop’ position. Just remember to buy the identical unit as the uniquely shaped lugs slide into distinctly different angled recessed grooves along the base of the bolt. Note, the earlier angled 'pitched roof' shaped lug was arguably more time consuming and costly to machine, hence the switch to the easier 'rectangular' format on recent versions.

How to remove and replace the bolt guide / ejector lug assembly - simply unscrew the mag housing’s rear retaining screw (it threads into just behind the raised ejector lug) whilst a protruding lip slips into a slot beneath the breech. Remove the bolt and the ejector assembly thereafter slips out towards the butt. Insert the replacement, position the front lip inside the recessed slot, and screw in the mag housing's rear retaining screw - easy.

If the mentioned leading edge of your ejector lug’s fine but you still experience erratic cartridge or spent case ejections then carefully observe the rim’s contact edges of the twin angled claws for sign of obvious wear – replace if necessary. Ensure that you slightly re-tension the claw’s sprung retaining clip (by carefully compressing it between your fingers) prior to re-attaching it. Note, if the clip’s lost some of its power to firmly hold the extractors then, in turn, the case won’t be held tightly enough against the bolt face for it to be kicked free by the ejector.

How to remove and replace the bolt’s twin ‘claws’ - carefully prise open the retaining clip (e.g. with a fine pointed probe) such that the ends just slip over and off the sides of the claws. Carefully note the relative positions of the different shaped claws, then install the new replacement set. Remember to lightly re-tension the retaining clip prior to re-fitting. Note, I hook one end of the clip in its seated position over one of the claws and then use a sharp probe to gently pull the other end into its seated position.

If your mag randomly miss feeds than check to see if the ends of the spring are identically bent / shaped in addition to slightly re-tensioning / stretching the spring. Also, bearing in mind that the follower’s bent end bits might be ‘catching’ on the mag’s inner walls, minutely bend them until miss feeds either occur less frequently or are hopefully eliminated.

Note, simply re-tensioning the twin ‘claws’ sprung retaining clip thankfully resolved my cherished Brno’s ejection problem.

+1 this one Missed or Kieth

I shall have a look see at my model 2 Brno for these in the near future. If you could get some pics up the aforementioned instructions this will no doubt aid the processes further.

Again as others have said... Thank you for this post and welcome to AV

[trevort]

My CZ 452 occasionally leaves a case in the chamber. I then think its time for a clean and we're good to go before it happens again after a while.

This sounds like the problem you describe. I'm too much of a klutz to even attempt to take the bolt apart tho!!

Thanks for trying to help

[Knackers]

Thanks for that and welcome to the forum. My Brno model 2 has seen upwards of 25,000 rounds in the last 25 years and only in the last 4-5 years did I ever have ejection problems that always come good with a clean. That being said, it will/must wear out eventually.

[Camel]

Knackers, I had troubles with my CZ 453 not ejecting some cases and have been getting the occasional failure to fire, I think that Keith or the blokes at Abelas who supplied my last shipment of ammo would have had burning ears as I was blaming the ammo for the troubles.
After I got the shits good and proper, ranted and raved, (luckily I was on my own at the time), I got the thinking cap on and investigated my extractor and the collar that holds them under tension. I took the extractor out and carefully filed a small amount out of the inside that sits into the groove on the bolt, squeezed the collar in a little, (carefully) and all my ejection troubles went away. I then took the bolt apart and took a very small amount off the part of the firing pin that hits to stop it going too far out of the bolt face. Now the firing pin tip comes out level with the end of the bolt face, and guess what ? the miss fires have stopped and Keith can now have cool ears.

It seems that you can wear out the end of the firing pin, especially after around 80,000 rounds.

[Knackers]

I was going to ask how many rounds go thru one of your rifles before you replace it.?
My 25,000 odd rounds sounds a lot, but that only works out at two bricks a year.