CZ-75B Failure To Feed

DrSpaceJam

DrSpaceJam

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I'm looking for some advice on my CZ-75B having failure to feed issues.

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What occurs several times every magazine (averages 2 to 3 times) is the round won't fully seat itself in the chamber after the previous round. Extraction is fine and the cases eject a good distance. This problem also occurs when closing the slide release sometimes.

This problem first cropped up a few months ago during a match. Yesterday I put a new recoil spring in it and took it shooting but the problem persists. Here's a few things I've tried, and none have eliminated the problem:

  • Thorough cleaning, especially of the feed ramp
  • Multiple different magazines (5)
  • Different ammo (handloaded IDPA rounds and factory, mostly 124 grain but also some 115 grain)
  • Replaced extractor spring

This gun has never had any issues, but it's also been used a lot. Any ideas on what else I can try with it? I'm considering replacing the mag springs, but it feels unlikely for five different mags to have that issue at once, especially as two of them are used far less than the other three and still exhibit the same issue.

Thanks for any help.
 
These magazines, are they as old and worn as the gun? Have you tried a new magazine? Vlad has excellent advice, but if it's also doing it with factory?
 
Vladthepes said:
Do you use reloads? If yes, that is the problem! I had to buy a special resizing die for the same problem! (it resize a bit smaller)
Click to expand...

I do mostly shoot reloads, the same thing for six years. I don't know why the problem would develop now, though I did suspect my ammo. But I tested it with factory ammo and it causes the same problem. Can you explain the die that you needed and what problem it resolved?

Painkillers said:
These magazines, are they as old and worn as the gun? Have you tried a new magazine? Vlad has excellent advice, but if it's also doing it with factory?
Click to expand...

All the mags are around the same age, but three of them have been used for many thousands of rounds more than the other two, which are almost new. I'll see if I can grab a CZ mag from somebody to try it with next time I go out.
 
Why not have a gunsmith (or you if you have the know how) grind or polish the feed ramp? My bro had an issue like this as well and we were told it was the ramp and wasn't going to get resolved with just a cleaning.
 
DrSpaceJam said:
... I tested it with factory ammo and it causes the same problem. ...
All the mags are around the same age, ...
Click to expand...

If *exactly* the same malfunction occurs with factory ammo, then it's not due to your reloads.

Have you scrubbed the breech face, barrel hood, extractor, and chamber?

Are you certain the problem occurs with every different magazine you have? Testing with a new magazine would be ideal (feed lips or possibly the springs are tired).

If that doesn't get you anywhere, try removing the recoil spring and hand cycling dummy ammunition made to exactly the same spec. Or use live ammunition if you must - Either remove the firing pin (preferred) or do it at the range where it's safe. Slow cycling might reveal where the rounds are binding. It could be the breech face, barrel hood, chamber, or possibly sliding under the extractor.
 
RHMadness said:
Why not have a gunsmith (or you if you have the know how) grind or polish the feed ramp? My bro had an issue like this as well and we were told it was the ramp and wasn't going to get resolved with just a cleaning.
Click to expand...

If I can't resolve it in another manner, I'll be taking it to the gunsmith. I'm starting to suspect this is the problem.

alpining said:
If *exactly* the same malfunction occurs with factory ammo, then it's not due to your reloads.

Have you scrubbed the breech face, barrel hood, extractor, and chamber?

Are you certain the problem occurs with every different magazine you have? Testing with a new magazine would be ideal (feed lips or possibly the springs are tired).

If that doesn't get you anywhere, try removing the recoil spring and hand cycling dummy ammunition made to exactly the same spec. Or use live ammunition if you must - Either remove the firing pin (preferred) or do it at the range where it's safe. Slow cycling might reveal where the rounds are binding. It could be the breech face, barrel hood, chamber, or possibly sliding under the extractor.
Click to expand...

It's all been scrubbed and some of the components were cleaned with an ultrasonic. I tested with my five marked magazines and the issue replicates pretty much perfectly with all of them. I'll try some testing with snap caps and dummy ammo and cycling it by hand slowly and quickly and see what happens.
 
I'd also be looking for barrel lug/frame wear on the gun. If the fitment is worn/loose it can cause feeding problems. Mind you, it would have to be really worn?
 
I've given it a pretty thorough once-over and I don't see anything that looks battered or clapped out. It's obviously well-used but not chewed up. I did attempt slowly hand cycling it and this virtually always produces the same error: the round catches while moving off the magazine. The nose will be entering the chamber and then it will get stuck in place (like the picture in the first post). If I give the rear of the slide a slap, it then closes and goes into battery.

I have no idea what might be causing this. The chamber is clean and the extractor appears to be engaging the rim (it also works perfectly when I cycle the slide after it gets into battery). Any idea on the potential failure points here? It does this with multiple types of bullet (round nose, flat nose, etc.) and lengths.
 
If handloading several times fires brass, your cases may have grown some length enough to not fully chamber. Look up proper overall case lengths for your caliber and trim your brass. Likely your chamber may be cut a tad too short where even some factory rounds may be too long.
 
Your photo shows a round not chambering at all, yet you state it won’t fully seat in the chamber. Which is it? Big difference between not chambering at all and not fully seated. Hard to diagnose not knowing the exact circumstance.
 
DrSpaceJam said:
I've given it a pretty thorough once-over and I don't see anything that looks battered or clapped out. It's obviously well-used but not chewed up. I did attempt slowly hand cycling it and this virtually always produces the same error: the round catches while moving off the magazine. The nose will be entering the chamber and then it will get stuck in place (like the picture in the first post). If I give the rear of the slide a slap, it then closes and goes into battery.

I have no idea what might be causing this. The chamber is clean and the extractor appears to be engaging the rim (it also works perfectly when I cycle the slide after it gets into battery). Any idea on the potential failure points here? It does this with multiple types of bullet (round nose, flat nose, etc.) and lengths.
Click to expand...

A stumper for sure. I've read that you have new springs in...the slide and frame are dissimilar materials, is there any galling on the slide rails impeding its travel?
 
My SP-01 was a picky eater as well when I got it, especially with reloads. Jammed in the exact same way. I found that the magic length was 1.124" COAL and it fed just fine. Longer or shorter by .010 tended to make it more prone to FTF as pictured.

Might also want to consider a new fresh slide spring if you are over 5000 rounds on the pistol.
 
DrSpaceJam said:
... Any idea on the potential failure points here? ...
Click to expand...

Did you replicate the issue with a new magazine? Hopefully it's just your mag springs and/or feed lips are tired.

What would you say the round count is on the frame and barrel? They don't last forever...

Beyond that, diagnosis gets more involved. As the cartridge moves from the magazine to the chamber, it's typically pinched between some combination of the breechface, feed ramp, barrel hood, and extractor. Give everything a good clean, and degrease enough so that sharpie marker will stick to the surfaces. Paint each of the above surfaces with sharpie, and then hand cycle dummy ammunition (made to the same spec as your reloads). You'll be able to see exactly where the cartridge contacts the guiding surfaces, hopefully also showing where the friction is coming from. Running a cotton swab over these surfaces should be perfectly smooth and snag-free.

The way the cartridge is binding in the photo, it looks like it is having trouble sliding up the breechface / under the extractor.
 
CeeZer said:
Try new mag springs, also a stronger recoil spring.
Click to expand...

I put in a stronger recoil spring recently and it's still having the same issue. I'm going to have to try somebody else's mags or something but it seems unlikely five magazines will all produce the exact same failure at the same time, especially with two having many less rounds and being newer.

easy said:
Your photo shows a round not chambering at all, yet you state it won’t fully seat in the chamber. Which is it? Big difference between not chambering at all and not fully seated. Hard to diagnose not knowing the exact circumstance.
Click to expand...

I apologize if the terms I'm using don't make sense, I don't know anything technical about guns. I'm just an end user. The failure state in the photo is the one that always occurs with almost no variance.

Painkillers said:
A stumper for sure. I've read that you have new springs in...the slide and frame are dissimilar materials, is there any galling on the slide rails impeding its travel?
Click to expand...

Not that I can see, I just cleaned it again.

aric84 said:
My SP-01 was a picky eater as well when I got it, especially with reloads. Jammed in the exact same way. I found that the magic length was 1.124" COAL and it fed just fine. Longer or shorter by .010 tended to make it more prone to FTF as pictured.

Might also want to consider a new fresh slide spring if you are over 5000 rounds on the pistol.
Click to expand...

My rounds are a lot shorter than that but they've never caused issues. The issue persists when I use all kinds of ammo lengths from factory rounds as well.

alpining said:
Did you replicate the issue with a new magazine? Hopefully it's just your mag springs and/or feed lips are tired.

What would you say the round count is on the frame and barrel? They don't last forever...

Beyond that, diagnosis gets more involved. As the cartridge moves from the magazine to the chamber, it's typically pinched between some combination of the breechface, feed ramp, barrel hood, and extractor. Give everything a good clean, and degrease enough so that sharpie marker will stick to the surfaces. Paint each of the above surfaces with sharpie, and then hand cycle dummy ammunition (made to the same spec as your reloads). You'll be able to see exactly where the cartridge contacts the guiding surfaces, hopefully also showing where the friction is coming from. Running a cotton swab over these surfaces should be perfectly smooth and snag-free.

The way the cartridge is binding in the photo, it looks like it is having trouble sliding up the breechface / under the extractor.
Click to expand...

I'm going to try to borrow a mag from somebody at the range next time I'm there. For round count, I'd say this has well over 10k rounds through it. I'm also suspicious that there's an issue with the extractor or the breech face. I can't feel anything, but sliding a round into the extractor with the slide removed from the frame by hand (I hold it upside down, sorry if this is disorienting) extremely tight. I can't feel anything out of sorts, but I'm wondering if the geometry of the extractor is wrong or something.

Talltimber1 said:
It is catching on the slide stop.
Is it worn out?
Common CZ failure point.
Click to expand...

I've never heard of this. How do I recognize or diagnose it? What tells you the slide stop is worn out? It looks ok to my totally untrained eye.
 
I understand a bit better now. Thanks for the clarification.
These types of feeding issues are most often caused by weak magazine springs and/or feed lips deformation.
I’m ruling out the fees ramp issues cause it’s been working fine for thousands of rounds.
An extra power recoil spring would help if you’re going to replace it.
Finally, check that the magazine spring is oriented properly in the mag body and not installed backwards, or upside down.
 
DrSpaceJam said:
... I'd say this has well over 10k rounds through it. I'm also suspicious that there's an issue with the extractor or the breech face. I can't feel anything, but sliding a round into the extractor with the slide removed from the frame by hand (I hold it upside down, sorry if this is disorienting) extremely tight. I can't feel anything out of sorts, but I'm wondering if the geometry of the extractor is wrong or something.

...I've never heard of this. How do I recognize or diagnose it? What tells you the slide stop is worn out? It looks ok to my totally untrained eye.
Click to expand...

If it's "only" 10k rounds, that's probably not the issue. And you should be able to see the cartridge rubbing against the slide stop if that's an issue. Or, mark the brass with sharpie and cycle it through - The slide stop interference should leave a clear mark on the side of the cartridge. The photo makes it look like it is clearing the slide stop, but you should rule it out by checking.

However, the breech face / extractor sounds like an issue: There should be some resistance sliding the round up under the extractor, not a lot. It would be best to compare yours to a properly functioning 75 so you can feel the correct resistance.

Does the extractor move properly in its groove in the slide? Does it have any sharp edges that could catch on the brass? You might need to remove it from the slide to check properly - Look for uneven wear and/or burrs where the cartridge makes contact.
 
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