527 help - light primer strikes

[Cat Whisperer]

Need help in determining cause of light primer strikes in my CZ 527 American in .223 .

Relatively new.  I'm 2nd owner.  Good price.  Exceptional accuracy!  Good lookin' gun, handles well.

About 10 rounds into string it will occasionally give light strikes, not firing the round.  Gets worse.  

Observing it fire, nothing from the outside of the gun appears abnormal.

Primers are lightly dented, multiple strikes sometimes will fire.

Disassembly of round and primer reveal normal ammo, two brands - PMC and LC-92.

We've cleaned the bolt assembly.

Question?  Is the wear on the firing pin from the sear (pictured below) normal?

[R.W.Dale]

I had a similar problem with my 527 carbine but in my case the problem turned out to be CCI primers After switching brands problem solved.

[Cat Whisperer]

I had a similar problem with my 527 carbine but in my case the problem turned out to be CCI primers After switching brands problem solved.

Thanks for the quick response!  I've not yet tried hand loads, CCI are the hardest primers out there - which I've used all my life - not an option for me to change when I get enough brass formed in this chamber to start serious reloading for this rifle.

I just sent the link to "Master Gunsmith" Mike at CZ-USA.  Seeing LeftoverDJ's post on similar problem with his 7.62x39 it may be that I will have a similar solution.

[hunt127588]

Have you disassembled the bolt and cleaned all the oil? My CZ 550 was packed in quite a bit of oil (or cosmoline) when it came ot me. Try cleaning everything up and shoot again.

[Cat Whisperer]

Have you disassembled the bolt and cleaned all the oil? My CZ 550 was packed in quite a bit of oil (or cosmoline) when it came ot me. Try cleaning everything up and shoot again.

Good suggestion, thanks.  I forgot to mention that was the first thing we did.  Didn't help though.

[Cat Whisperer]

As I said, yesterday I sent the link to this thread to Mike at CZ.

Got this reply when I got home from work today:

"I am sending an extra-power striker spring in the mail, ETA 3-5 days."


WOW!  That's service!

Tune in tomorrow (or the next day or three).

[Brithunter]

Not sure about the newer ones but it used to possible it seems to assemble the bolt firing pin incorrectly causing this problem. Our club sec it seems did it with the club 527 Fox some years back.

[Cat Whisperer]

Not sure about the newer ones but it used to possible it seems to assemble the bolt firing pin incorrectly causing this problem. Our club sec it seems did it with the club 527 Fox some years back.

The former owner only ran 40 rounds through it & traded it in.  I have had the bolt apart but not the firing pin assembly.  I'll check that out when the new spring gets here.

Thanks!

[Simple Man]

I think CZ's service is some of the best in the business IMHO.

[Cat Whisperer]

I think CZ's service is some of the best in the business IMHO.

Just got the spring in the mail (with attached business card).
Now to install it.  Rats! Rain predicted for this weekend.

[Cat Whisperer]

The spring LOOKED extremely large, so I e-mailed Mike and inquired to how to replace it.  He sent this:

Do not drive out the pin. Instead, rotate the bolt sleeve (black knob on back of bolt) a 1/4 turn counter clockwise, to un-cock
the bolt(firing pin should protrude from the bolt face). In this mode the bolt handle will now be free to pull out of the bolt body.
 With the handle removed, the striker asembly will now be free to come out to the rear. The striker spring is retained by the silver keeper on the end of the assembly. Pulling the keeper slightly to the rear, and rotating it a 1/4 turn in either direction will release
the spring. Note: The keeper is under heavy spring pressure. Be careful not to loose the keeper. Assemble new spring in reverse order.

IT WORKED, the extended springs side-by-side were similar, with the new one longer (one or so more turns) and what appeared to be heavier wire.

I recommend a large vice and a 6mm (1/4" drive) deepwell socket to reassemble.

THANKS TO MIKE AND CZ!

The new spring feels stronger and sounds more definite in action.  Snow now predicted for Saturday though.

[Simple Man]

Glad to hear it all worked out for you. Thanks for sharing this with all of us cause you never know when someone else might have this same problem.

[hicard]

I'm having the sam problem.  How do I get a heavy duty firing pin spring?

[Cat Whisperer]

I'm having the sam problem.  How do I get a heavy duty firing pin spring?

Before you jump to conclusions:
a) switch ammo - that eliminates one possibility.
b) clean the bolt (inside) - mine was super clean, others weren't.

Then google CZ USA  - email their customer service.  They were GOOD to me!