P-07 various issues

[M1A4ME]

I never paid attention to how off centered my feed ramp on the P09 9MM was till I was looking at the pictures of all three.

I've got a P07 9MM barrel in a cabinet I can't get to right not.  I'll try to remember to take a look at it once I can get to were that cabinet is.

Yeah, get it to the range and see how it does.

[Wayward_Angel]

I did two more modifications which I also do with all my 1911's which helps feeding and cycling a lot. I polished the breech face to make it easer for the cartridge to slide up underneath the extractor. (Did that with 1000 grit and polishing compound, I did not increase headspace by any significant amount)
Second thing I did is taking the extractor out and polish the edge where the recess of the rim slides on ( I did NOT smoothen the edges of the actual claw but I polished the outside of the claw to a mirror finish, without changing any angles).

I cycled it with a few dummy rounds and I think it feels a lot smoother now. If it really helps solving my FTF's - next time on the range will tell...

[Wobbly]

Hey guys, just bought a P-07....

Lubed and cleaned the gun every 50 rounds, shot 350 rounds through it and got many failures to feed, the round would get stuck halfway into the chamber, I have to give the slide a smack to get it into battery, sometimes its so bad I have to eject it.

Instead of pounding your gun to get it to go into battery, you need to stop and set those rounds aside and do a "post mortem" back on the bench. With the barrel removed from the pistol.... each round should drop all the way into the chamber AND THEN fall right back out using ONLY the weight of the round itself.

If not, then you are running the risk of having the gun fire out of battery, which can not only hurt you, but completely destroy the polymer P07.



I agree, S&B is typically wonderful ammo. But, between the out-of-control Russians and Covid lock-downs, all ammo plants have been running non-stop 24/7/365 for years. This includes new staff and lower QC standards. Apparently shipping ammo is more important than customer safety.

Testing like this takes seconds and will give you a definitive answer. If you have a box of 50 rounds and 49 fall in & fall out then it can't be the gun. And if you do the same test on your other precision 9mm handgun barrels, I bet the offending rounds will also fail in other 9's with fully supported chambers.

Follow that up with cartridge measurements using the SAAMI drawings (on-line). It's important to remember that those SAAMI dimensions for the cartridge are Maximum numbers. IOW, the 0.380" case mouth is obsessively oversized at 0.381". A head diameter of 0.392" is pure scrap.



Bottom Line: You don't need to ask us anything. You need to start doing some of your own product testing.

[Wayward_Angel]

Bottom Line: You don't need to ask us anything. You need to start doing some of your own product testing.

But I already did that, I've been reloading for many many years now and I know how to test ammunition. As mentioned in my previous post I reloaded 50 rounds with a 124 grain Fiocchi bullet at 1.141 OAL, 4.8 grains VVN340 and did the ''plunk test'' with every single round and had the same issues of the slide not going into battery thrice at the range, plus several instances of the pistol cycling extremely slowly.

This load is as vanilla as its gets, velocity is 1160 fp/s. I have thousands of rounds of this load through my Glock 17, my P320, my Beretta 92FS and my 1911 9mm. I also tested what the max OAL for this bullet in this barrel is, it is above 1.200 which is pretty long.

Not to mention I can also easily reproduce that malfunction with an absolutely spec round just by cycling it with my hand as you can see in one of the pictures I posted - a malfunction I cannot induce with any of my other pistols.

And I want to mention here that I don't run the risk of getting an out of battery detonation as the the round gets stuck way before the hammer is even cleared by the slide.

[RSR]

Try some other mags.  Could be a bad batch.

Run your gun super wet with lube to ensure nothing hanging up on slide.

Try running +P rounds and see if the same happens.

Etc.

Or just call CZ and let them service/repair the gun.

[Wayward_Angel]

Try some other mags.  Could be a bad batch.

I don't think its the magazines, because I just loaded the gun, removed the magazine, pulled the slide back almost
ejecting the cartridge and then letting it gently go forward again. It hangs up just before going into battery.
No idea what causes the slide to stop, the chamber is smooth, I polished the breech face, I polished the extractor - the only thing I can imagine is that the extractor spring is so stiff it stops the round from coming up.

No magazine:

[Wayward_Angel]

Huh, maybe I fixed the pistol. I went to the range and shot 2 magazines of my reloads (they were already closing so I could not shoot more rounds sadly) without a hiccup, no slow-mo cycling, no FTF's and ejection pattern was also consistent. Everything felt good.

I reserve final judgment until I have 100 rounds more through it but maybe.....

[M1A4ME]

Huh, maybe I fixed the pistol. I went to the range and shot 2 magazines of my reloads (they were already closing so I could not shoot more rounds sadly) without a hiccup, no slow-mo cycling, no FTF's and ejection pattern was also consistent. Everything felt good.

I reserve final judgment until I have 100 rounds more through it but maybe.....

Sounds good.  You may have gotten it with that breech face polishing job.  Sometimes the little (or unusual) things make a difference.

Hope it keeps on working for you.

[Wayward_Angel]

I think I fixed it - just shot 150 rounds of S&B 115 & 124 grain, my own 124 grain reloads and even my Sierra 115 grain HP +P loads.
No hiccups whatsoever, no slow motion cycling, no nothing.

Not sure if 150 rounds is enough to call it fixed but I feel good about it. 

[Wobbly]

Some CZ's simply require a break-in period.

https://czfirearms.us/index.php?topic=120249.0

[Wayward_Angel]

I read about CZs needing a break in period but never about the polymer variants, the 07 and 09. People I've talked to had their 07 and 09 running perfectly right out of the box.

I think some minor problems stacked resulted in taking enough energy out of the slide during cycling to cause FTF's. The edge of the extractor was slightly rough, so was the breech face and the feed ramp right where it transitions into the chamber was a bit on the rough side as well. Add some dirt from a couple dozen shots and standard power 9mm and the system is going to slow down and struggle.
Now that all surfaces the cartridge is coming in contact with are polished to a mirror finish one wipe is enough to remove all of the dirt and brass residue.

[Born2vette]

Glad to hear.  Got my P-07 out today and ran 175 rounds (150 Scorpion 124 gr fmj and 25 Gold Dot 124 gr + P) flawlessly.  Its an easy pistol to shoot well.

[steves2]

You're a very patient person!
It doesn't sound like your pistol should do this, and not with S&B 124 gr ammo!
CZs do have tight chambers, but this sounds a bit extreme.
Contact CZ.

[M1A4ME]

I've never had a CZ with break in issues either but I'm sure every now and then one if made with a collection of parts that require a little more "wear in" than most.

I did have one that needed the feed ramp polished and I did that and fixed the occasional failure to feed it would have (bullet nose hit the feed ramp and forward motion stopped right there.)

Keep us posted either way, continued fun at the range or more attempts to diagnose/cure it's problems.  I've got a lot of CZs but if I ever run across another P07 in .40 S&W it'll probably have to come home with me for a back up/spare.

[SI VIS PACEM PARRABELLUM]

I've got a lot of CZs but if I ever run across another P07 in .40 S&W it'll probably have to come home with me for a back up/spare.

A quick search on Gunbroker for CZ P-07 .40 shows 2 P-07's in .40 S&W. One is a DUTY model and the other is a second gen version.