View Full Version : CZ 527 7.62x39 to rechamber?

Lawyer Daggit
June 22, 2006, 02:15 AM
I have a CZ 527 in 7.62x39. The rifle has had a couple of trips to the gunmith to overcome a problem associated with failure to fire with civillian ammo, which I understand to be attributable to the manufacturer building the rifle to eastern block specs which differ from SAAMI specs for this round.

A stronger firing pin spring has lead to a marginal improvement, but I cannot live with frequent misfires.

I do not want to have the gun re-headspaced as I like the iron sights on this carbine and even if removed I do not want the dovetail sitting at an un natural angle.

Is anyone aware of any other 'fixes' that will enable this gun to work?

Alternatively, what should I rechamber the gun in? my thoughts are a PPC round or 6.8 SPC. Which would be the more viable as a conversion on this platform? what is involved? what other chamberings would you consider?.

If rechambering I would ideally like to be able to utilise as much of the original firearm as possible to keep costs down.

The gun is intended to be used on wild pig and deer.

June 22, 2006, 06:56 AM
This is the first report about the 527 vs US ammo that I have heard. One idea that comes to mind would be new, slightly longer firing pin. It is possible that there may be a way to adjust the firing pin protrusion on a 527 but I don't know. It might be worth investigating. To convert the rifle to a 6PPC or a 6.8, a new barrel would be required since the bore, at 7.62mm is already too big. If you handload, it might be possible to neck or partially resize cases fired in the gun, thus fitting them to the chamber with the rear end against the bolt face.


June 22, 2006, 11:28 AM
Any semi-skilled smith can plug the old dovetail, and mill a new one, so it will never be noticed.

Also, every 527 Ive seen in 7.62 shoots both SAAMI and Com-Bloc ammo just fine.

June 22, 2006, 11:59 AM
Wait a sec - it won't shoot stuff like Corbon, or won't shoot stuff like Monarch? What about Wolf? Is the problem definitely light primer strikes? Because I understood the "civilian" ammo, as you say, to have softer primers, not harder, than milsurp or so-called 'surplus', so I can see there maybe being a problem with 'surplus' ammo, but not 'civilian' - how are you defining 'civilian' here? Have you tried Corbon, or reloading? I would think there'd have to be a good fix for making it work, short of rechambering. What do the go and no-go gauges say right now - is it in fact headspaced too long or just right? If it's too long, it's too long, and maybe rebarreling / rechambering would be better than turning the barrel down. But if the guages say that headspace is correct, surely there's a spring somewhere (or as the man said, a longer firing pin), that will make it work. But failing all that, you might look at 6mm BR, 6mm PPC, 6.5 Grendel, 6.8 SPC. Actually, if you don't want to pay for another barrel, you'd be better off just turning down the existing barrel and sticking with 7.62x39, and as mentioned, re-milling some mount grooves. Hmmm..

June 22, 2006, 01:11 PM
I agree with most, not all, of the views expressed.

Assuming it has proper headspace (have a go-no go gauge?), try to identify why it is misfiring before applying any new solutions to a problem that may or may not exist. Light primer strikes could be either not enough firing pin protrusion or garbage built up inside the bolt. If the rifle has not been altered, this is a job for CZ to fix. If you have modified the firing pin, I would still sent it to CZ for repair.

If your rifle has excess headspace and you want to continue to use the iron sights, a gunsmith can set the barrel back a full turn (so that the sights are still in the correct place) and recut the chamber for the proper headspace.

I guess what I am getting around to here is to take the gun to a qualified gunsmith, explain the problem, and let him suggest the proper way to repair the problem.

If you do decide you want a new caliber, you will just be more confused if you ask others for the best caliber to change to because you will get other people's opinions. Get a copy of Cartridges Of The World, look through it, and decide what you think is the next cartridge. Or trade the gun in on another rifle.

June 22, 2006, 07:58 PM
If you rechamber to a PPC round, you're going to have to handload. If you're willing to handload, you hould have no trouble making the 7.62x39 work.

I had a 7.62 AR-15 Upper that wouldn't fire much of the imported ammo. Winchester stuff worked fine. AKM/SKS rife have firing pins that hit like a ton of bricks. The AR just didn't have the "oomph".

Lawyer Daggit
June 22, 2006, 11:13 PM
I will talk to a gunsmith about the problem, but I tend to find that good ones are very thin on the ground here in Australia and I often find you are better off getting an idea about possible solutions by talking to other 'knowledgeable types' before talking to them.


Jim Watson
June 22, 2006, 11:15 PM
You cannot "rechamber" to a smaller calibre.
You would have to replace the barrel.
I bet a CZ for 6.5 Grendel (6.5 PPC Improved) would be a good shooter.

June 23, 2006, 12:23 AM
I also have the problem of misfires occasionally with American ammo and my CZ 527 7.62x39. I heard about it from someone else and they recommended going to CZ for a different spring, which I've received but haven't installed yet. Wolf and the light doesn't seem to experience the same problem.


Lawyer Daggit
June 30, 2006, 12:55 AM
I have now been told by a couple of gunsmiths that they would not either fit a stonger spring or longer firing pin because of concerns about headspacing- ie while the gun would go 'bang' their concerns regarding headspacing have not been addressed.

June 30, 2006, 11:41 AM
If the smiths are concerend about the headspace, then address that issue. If your CZ has excess headspace, have the barrel set back one full turn and recut the chamber. Then go after the firing pin issue. While all the advice you get on this forum may help you hunt down solutions to obscure problems you may eventually run into, a gunsmith can give you real advice because he is trained in how to identify and repair hardware malfunctions.

All the advice you get here may be comforting, but it tends to ignore the fact that you have not had the weapon inspected by a gunsmith and listened to his proposals for repairing the problem. Sorry to sound so stern, but if you broke your leg, you would go toa doctor for help. But with a weapon you go to opinion-mongers?

June 30, 2006, 12:05 PM
Call CZ USA and tell them the problem they might fix it free of cost. If I have a problem with a factory gun I call the company first instead of taking it to a gunsmith and have to pay for it. Every firearm that I have had sent back to the factory has been fixed free of cost.

Lawyer Daggit
July 2, 2006, 01:55 AM
Pesta 2, the CZ 527 in 7.62x39 is no longer imported into Australia following a recall because of this issue. I can tackle the local agents and get the gun replaced with one in another chambering (they have offered a .223) and have consulted two local gunsmiths regarding this problem.

I am trying to find a solution that will give me either a useable CZ527 in 7.62 x 39 OR another chambering that is simmilarly potent, because a .223 swop does not really replace the 7.62x39- it gives me a nice 'walkabout' varmint gun but not a feral pig gun.

Consulting colleagues regarding this type of problem on a chat line can be invalueable, because often people come up with alternatives that so called experts do not know about.

July 2, 2006, 11:12 PM
I have a CZ 527 in 7.62X39 and it will eat any and everything, some more accurate than others but never any light strikes. May need to go back to CZ.