CZ P07 FAILURE TO RETURN TO BATTERY

[SI VIS PACEM PARRABELLUM]

On any gun experiencing this issue the first thing I would do is replace the recoil spring

Read the Op's entire opening post. This is clearly an ammo related issue due to the fact that CZ's have short chambers. The issue only arises with one particular brand/type of ammo. The gun simply needs to go back to CZ and they will recut the chamber so this will no longer be a problem. The P-07 is a tightly sprung gun as it comes it's a chamber issue.

[recoilguy]

He never got to say what the second thing he does is and it might be send it back for an recut at CZ. who knows?

The first thing I do when something like this happens is swear and throw bullets around.
Doesn't do a lot of good but in my opinion Im not doing the wrong thing.
I don't think replacing the recoil spring will hurt,
if it doesn't help, the gun has a new recoil spring and he can move on to the second thing he does. He hasn't plunk tested it,

Not everyone knows what the problems clearly are, that's why they ask here and why they post here. Replacing the recoil spring is not going to exacerbate the problem.
might just be therapy. Poor guy just said what he does first.

RCG

[SI VIS PACEM PARRABELLUM]

He never got to say what the second thing he does is and it might be send it back for an recut at CZ. who knows?
I don't think replacing the recoil spring will hurt,
if it doesn't help, the gun has a new recoil spring and he can move on to the second thing he does. He hasn't plunk tested it,

Not everyone knows what the problems clearly are, that's why they ask here and why they post here. Replacing the recoil spring is not going to exacerbate the problem.
might just be therapy. Poor guy just said what he does first.

RCG

The first thing that should happen is the plunk test especially on a CZ when we know the chambers run short. I'd be certain of proper ammo fit before I started swapping springs. Just suppose a new spring provides enough power to close the slide just enough to cause an out of battery failure. Then you've got a whole new set of circumstances.
I'm not trying to bust anyone bubble here but there's just a normal flow of diagnostics that should be followed for safety's sake.

[recoilguy]

Safety should always be the first and the most important consideration.
thanks for the clarity, I misunderstood your intent. that's the problem with reading stuff while having the day I'm having.
You assume everyones tone is the tone you are currently dealing with in real life, I apologize.

RCG

[Wobbly]

Read the Op's entire opening post. This is clearly an ammo related issue due to the fact that CZ's have short chambers. The issue only arises with one particular brand/type of ammo. The gun simply needs to go back to CZ and they will recut the chamber so this will no longer be a problem. The P-07 is a tightly sprung gun as it comes it's a chamber issue.

No, sorry, but I disagree. If it's the fault of the ammo (as I also suspected on my reading) then he simply needs to change his ammo. The nature of handguns is that not all 9mm ammo fits in all 9mm handguns. This is why we take our barrel with us when we are ammo shopping.

If you insist on only on-line ammo shopping, then be prepared to trade off the occasional box of 50 to a pal because not all ammo fits all guns. That's just the price you pay. Or you can come on here and ask for references first.

 

[inthevalley]

Read the Op's entire opening post. This is clearly an ammo related issue due to the fact that CZ's have short chambers. The issue only arises with one particular brand/type of ammo. The gun simply needs to go back to CZ and they will recut the chamber so this will no longer be a problem. The P-07 is a tightly sprung gun as it comes it's a chamber issue.

No, sorry, but I disagree. If it's the fault of the ammo (as I also suspected on my reading) then he simply needs to change his ammo. The nature of handguns is that not all 9mm ammo fits in all 9mm handguns. This is why we take our barrel with us when we are ammo shopping.

If you insist on only on-line ammo shopping, then be prepared to trade off the occasional box of 50 to a pal because not all ammo fits all guns. That's just the price you pay. Or you can come on here and ask for references first.

 

If the gun doesnt plunk with HST then the barrel should be returned to CZ and reamed or replaced. 124 HST is probably the most popular premium round on the market and IMO any quality handgun should run it reliably. My P-series guns run every factory hollowpoint and FMJ with no issues, they are superbly reliable in my experience.

I just plunked 124+p hst and 147hst in both my P07 and P09 barrels and they were as smooth as can be.

To Parabellum:
I agree plunk test should be the first step, but I disagree that changing the recoil spring is going to lead to any safety issue such as firing out of battery, the firing pin safety wont be released unless slide is pretty much all the way in battery.

If the gun is close to new then you are absolutely correct that there is no reason to considee the recoil spring, but if he bought it used or has a lot of rounds downrange that is a different story.
The reason I suggested the recoil spring is one of my P07s i bought used. It had a failure where it would occasionally lock back with rounds still in the mag, with 124+P HST. Changed the recoil speing and no more issue, with lots of rounds including over 200 hollowpoints downrange since. On other pistols such as a Grand Power P11 I have the worn out recoil springs give symptoms that sound very very similar to OPs.

[Wobbly]

If the gun doesn't plunk with HST then the barrel should be returned to CZ and reamed or replaced.

That is also a very good option.

[SI VIS PACEM PARRABELLUM]

To Parabellum:
I agree plunk test should be the first step, but I disagree that changing the recoil spring is going to lead to any safety issue such as firing out of battery, the firing pin safety wont be released unless slide is pretty much all the way in battery.

I didn't say it would definitely fire out of battery but yes they can get just close enough to fire without total lock up. I've seen it happen and had it happen and it will get your attention immediately. Another thing you have to be careful of is trying to force the slide closed either by hand or with heavier springs on rounds that don't headspace properly since you can induce bullet setback and that can be an attention getter as well.
I own many CZ's and some I no longer own and while they all had the typical CZ short chamber none of them ever failed to accept any factory ammo I tried and of course my reloads are tailored to the guns so there's no issue there. I do think that there have been some guns coming off the line in the past few years that have had chambers a bit shorter than average as I've seen some complaints of ammo not plunking in them while I know my guns plunk that ammo just fine. Case in point the ammo the OP is having issues with fits my barrels without issue. I use that round in my PCR currently.

[atxbell]

UPDATE PLUNK TEST:

Federal 124gr HST: Fail
American Eagle 124gr FMJ: Pass
American Eagle 147gr TMJ: Pass
Speer Gold Dot 124gr JHP: Pass

I ran 20 rounds of the Speer Gold Dot 124gr JHP Standard Pressure with zero issues.  One thing that surprised me was the amount of what looked like bullet fragments the cartridge left inside the chamber of the pistol.  They weren’t thin shavings but almost rounded crumbs.  Is this normal with this round?

[M1A4ME]

Shavings from the bullet (hitting something sharp as it moves fully into the chamber?)

Or shavings from the brass where it catches on something as it's being fed into position to be pushed into the chamber?

If the bullet is hitting up in the area between where the brass contacts the end of the chamber and where the bullet contacts the rifling is it hard to hand extract?  I've had an issue or three where what works in one (or half a dozen) pistols won't work in a particular pistol.  Usually it's a fight to get the slide pulled back if the bullet made contact and the recoil spring/slide jammed it as far into the barrel as it would go.

Even if it's a light touch sometimes you can see marks on the bullet.  Either one that goes around the bullet parallel to the case mouth just a small distance forward of the case mouth or little spots around the bullet where it contacts the lands of the rifling.  It should not make contact, but some pistols are made like the rest of them and won't work well with some cartridges/bullet weights/bullet profiles.

[atxbell]

I found a thread on SIG Talk that pretty much mirrors what I saw.  To quote a quote “Golden flakes, or ash colored flakes are generally just skeleton ash left from the burned powder flakes that didn’t get pulverized into smoke when fired”.  I’m gonna call it a non-issue for now but will update in the case it becomes one. 

SIG Talk Thread Link:
https://sigtalk.com/sig-sauer-pistols/33765-brass-shavings-breech-area-2.html#/topics/33765?page=1


I’m debating whether or not it’s worth it to test Federal 147gr HST Standard Pressure some more.  Out of the 50 rounds I fired I didn’t actually have any malfunctions, on the second to last shot I fired the slide felt a bit hesitant to return to battery however it did.  Assuming it plunks and I go through another 50 with zero issues would the 147gr HST be a good choice or is it too heavy for the P07’s relatively short barrel and will I essentially be sacrificing performance?

[lewmed]

 I had the same issue with the same ammo in my P07 when it was new.  I changed my carry ammo to Speer 124 gr gold dot +p and issues went away.

[CCWLearner]

I’m debating whether or not it’s worth it to test Federal 147gr HST Standard Pressure some more.  Out of the 50 rounds I fired I didn’t actually have any malfunctions, on the second to last shot I fired the slide felt a bit hesitant to return to battery however it did.  Assuming it plunks and I go through another 50 with zero issues would the 147gr HST be a good choice or is it too heavy for the P07’s relatively short barrel and will I essentially be sacrificing performance?

I have carried 147gr HST standard pressure in my P-07 for the past couple of years.  I have never had any type of malfunction when testing it or cycling through old rounds every few months.

Here's a Lucky Gunner test of the ammo from a S&W M&P9c with a 3.5" barrel:

https://www.luckygunner.com/9mm-147-grain-jhp-hst-federal-premium-le-1000-rounds#geltest

Here's ShootingTheBull410 testing the ammo out of some around 3" barrel 9mm pistol:

https://www.thetruthaboutguns.com/shootingthebull410-9mm-ammoquest-federal-hst-147gr/

So if it works in your gun, I wouldn't worry much about barrel length of the P-07 being a limiting factor for this load.

The only downside I have considered is the actual weight of carrying all of these 147gr rounds on my person.  If my math is correct, I could reduce the weight of my P-07 and my spare magazine by around 2 oz each if I switched to something like Underwood 90gr Xtreme Defender for my CCW.  Of course this would also be moving to an entirely different type of defense load... lightweight, high velocity, non-expanding, dumping energy by fluid displacement instead of expansion like a traditional hollowpoint.  Not sure I believe it's actually better, so I stick with the big, heavy, expanding bullets for now.  My Kore nylon belt is rated for 8 lbs so I'm good to go.

[BrandonP]

As for ammo recommendations, Speer GDHP has run well in all of my CZs. Target Sports used to have pretty great deals on case-sized quantities of it.

[Porcupine]

Read the Op's entire opening post. This is clearly an ammo related issue due to the fact that CZ's have short chambers. The issue only arises with one particular brand/type of ammo. The gun simply needs to go back to CZ and they will recut the chamber so this will no longer be a problem. The P-07 is a tightly sprung gun as it comes it's a chamber issue.

No, sorry, but I disagree. If it's the fault of the ammo (as I also suspected on my reading) then he simply needs to change his ammo. The nature of handguns is that not all 9mm ammo fits in all 9mm handguns. This is why we take our barrel with us when we are ammo shopping.

If you insist on only on-line ammo shopping, then be prepared to trade off the occasional box of 50 to a pal because not all ammo fits all guns. That's just the price you pay. Or you can come on here and ask for references first.

 

Buy a case of 147s for the P07, then buy another gun that likes the 124s.

Problem solved.