Another CZ858 lemon????

r.fallon

Regular
Rating - 100%
143   0   0
Location
Vancouver Island
Hi Gents
Awhile back I read a post of a guy who had his CZ 858 rifle self dissassemble on him. It seemed that the barrel and or gas block shifted on him, and the rifle was able to fire out of battery.
Forgive me if the details are not correct, but long story short I had a similar expiriance yesterday. After 15 rounds fired my forstock fell of and the gas piston was jammed all the way back. I assumed either the barrel has shifted forward or the gas block has shifted forward. I know, I know every one wants pics but it looks like any other 858 but without a forstock.

My question, is this a warrenty issue that with be covered by the distributer? My next question is this rifle was bought new through a private sale this summer will this void my warrenty?

Thanks RF
 
Is this one of the short 7.5 or 11.5 ones or the non restricted ones?
I have only seen this happening to the shorter ones.
 
You assume the barrel or the gas block moved?

Please take a look at your rifle and describe it's current condition for us.
 
The rifle is a Cz 858 NR . I inspected the rifle and could not find any evidence of the gas block or barrel shifting. What I did find is the under side of the gas tube is heavily worn on the small fwd nipple. I think that this would caused the piston to jam.
I also show the fwd stock off of the rifle but with the retaining pin in place.

I think what is the issue is that the gas block is installed incorrectly, this would cause misalignment of the gas tube housing with the piston and it would explain the forestock coming of the rifle while the retaining pin is in place.







If the rifle is defective from factory I would hope that the warrenty would be good.
Cheers
 
Thanks for the pics,

The only way the gas block can be installed incorrectly and have the rifle still run would be for it to be slightly canted. When you look at if from above, is it lined up with the sights or canted to one side?

Is there wear on the piston to match that on the handguard?
 
The cross pin for the lower handguard is still in place, looks like the handguard is worn (it's the type without the metal cap) where the pin passes through. If that's the part that fell off (the lower handguard) that's all the problem is. As far as the piston goes, if it's locking up on the upper handguard, I'm wondering if someone has stood on the front of the rifle, causing the furniture to deform.
 
Last edited:
The piston is coming into contact with the housing/guard over the piston.....which obviously should not be happening. Housing is probably bent or does not mount up right. The rifle is a battle rifle of a quality build, have had no issues with mine after thousands of rounds. I suspect previous owner bent something due to improper assembly at one time. There probably would not be wear on the piston because it made from a harder steel than the guard. Try stretching the spring a little, piston maybe travelling to far on it stroke coming out of place. Try firing without the upper guard under control to see if there is a malfunction, if no, then definetly guard is the problem.
 
Thanks for all the feed back guys.
In the first set of pics I tried showing the wear in the piston rod, all there is is some chrome splintering off, this could be from the gas block. The upper housing looks ok as far as damage/crookedness goes. Here are some close up pics after the rifle is assembled showing how much of a gap there is between the hand guard and the reciever. There was not a metal cap on the rear of the forestock. If there was how could the stock come off?
Also look at the pic of the gas block and the upper housing does this look OK?




I owned a rifle from the first batch of 858s that Wolverine imported (05-06?) I foolishly sold it in a moment of weakness, I only got around to replacing it this last year. This replacement rifle is not of the same fit, finish and quality.
 
The metal cap has a groove in it for the handguard cross pin. You remove the handguard by first driving the cross pin out of the receiver.

Gas block looks fine from that angle. Is it canted?
 
There should be a metal bracket that goes between the forend and the reciever that the pins slides through. That little bracket makes a nice tight fit. also I had to add a u shaped copper wire to the front of the forend in the bracket on the gas block to get a very tight fit.

As for the piston jamming no clue, but I have seen the forend fall of a cz 858 because someone lost the little bracket and worked loose when shooting.
 
It seems really odd to me that the piston could even come into contact with the upper handguard. The Guard fits ove the block, which has the piston running inside of it(the block). Now, unless the handguard was bent in/down by at least the wall thickness of the block, then the piston should never be able to hit the hand guard. It doesn't look like the handguard is bent that much, in fact you can see from one pic, that the end of the hand guard has the semi circular piece that fits over the block, then it is designed such that the hand guard is actually higher than the block outside dimension.

Is it possible the wear you're seeing under the hand guard is a big red herring? I'll take a look at mine when I get home tonight.

Also, maybe a photo/optical illusion, is your piston slightly bent? In your first pic, it looks a little to me (maybe the camera lense or something. Roll it on a nice hard surface see if it woblles any.

What rounds were you using? Did you maybe get some kind of freak hot round that blew the piston out of the block? I'm pretty sure if it was wearing that uch metal off the handguard, you'd have found filings galore in there when you took it off.

If you're close to the store, I'd take it back and get them to look at it. If not, give 'em a call and see what they'll do.

One other thought - post a pic of the piston inserted with the spring and I can compare to what mine looks like when I get home.
 
Last edited:
I had one of those it worked fine no issues but ended up selling it for a chrome lined FSN from Marstar.

I think the problem reported is a defect. I would suggest taking it in for service if you know who the importer is.
 
CRAFM is the CZ warranty center for Canada by the way. CZs warranty is pretty easy to deal with especially since there warranty center is here in Canada. I have an older CZ 858 and the barrel is totally canted off to the right. You can clearly see it, its pretty bad but for some reason it out shoots any SKS that’s gone up against and it embarrasses Mini 14s in accuracy so I just say f@#$ it in trying to get it fixed. Actually, I've noticed as its been getting older, the barrel has been slowly making its way to the center and I've had to adjust the front sight post. When I got mine new, the first time I used it the hand guard fell off too when I was shooting. I happened to be chewing on bubble gum at the time and had the bubble gum wrapper on the table. I just shoved it in the front part if the hand guard, popped it back on, and it stayed on perfectly. Haven’t had problems with it since. I even take it off once in a while to clean inside the hand guard. The only other problem I’ve had with my CZ 858 was the gremlin which was repaired using a garbage bag twist tie. 1000 rounds later and she still sings my favorite song.
 
Last edited:
Inside of my handguard is all painted black. But looking at it I just can't imaging how the piston would scratch the paint off like your pic and not have huge amounts of metal filings and paint flakes.
 
The gas block looks like it is square and where it should be. The ammo that I was using was the Czech m43 stuff. When the piston jammed it sprung back into place as soon as soon as I pulled the pin for the upper hand guard housing. The piston is straight , the hand gaurd has an ever so slight bend in it. I will contact the Canadian warrenty center for CZ and see what they have to say. Thanks again for every ones help.
 
Back
Top Bottom