Weird thing happened with my CZ P-09 while ejecting live round.

[Orion8472]

Just a little while ago, I was getting ready for bed and had my house gun with me, my CZ P-09 with 147gr Federal HST. I keep it unchambered. I decided to do a test feed, which fed normally, . . . dropped the magazine, and went to eject the round, but the slide was stuck closed. I finally got it unstuck, and tried another round. It, too, got stuck. It took a while and a lot of yanking, but got it out too.

Some 124gr rounds seemed to be okay. 115gr FMJ rounds were no trouble. Not sure what's up with the HST and this pistol, but I unloaded it and loaded up another pistol [with an accessory rail for the tactical light].

Any thoughts on this?

 

[Hometeached1]

I've read that CZ tend to have shorter chambers than most pistols, so the 147gr round OAL might be just long enough that it's contacting the rifling, causing to stick. Someone who knows more about reloading for CZs could give a better answer I'm sure. Hope this helps. I'm sure someone with more knowledge on this will come along soon.

 

[Lj1941]

Although you have factory ammo,I would do the "plunk test".With the buying frenzy it is possible some of the rounds are overlength and are jamming the bullet into the rifling. I would do this before I assumed any other problem. QC could be lax. This could cause an extreme overpressure situation and "KABOOM".

 

[Fremmer]

Can you shine a light into that chamber and check for burrs or something that might be snagging the case, and were there any marks on the case or bullet after ejection?

 

[gamestalker]

The first thing you need to do is color a round with a sharpie and chamber it. To avoid another frustrating experience, don't let the slide come down on it, so instead, take the barrel out and chamber the round by hand. And if it does get stuck, at least you'll have the barrel out and can easily tap the round out with a dowel or cleaning jag from the muzzle. When you remove the cartridge, look at the area where the sharpie has been rubbed off, that will be your problem area, and will most likely be the bullet jamming into the lands.

I've heard more than one person complain about the CZ having short throats. If in fact the bullet is jamming into the lands, I would most certainly not shoot that ammo, as pressures could go through the roof.

And you can also forget trying to seat the bullet deeper in that factory cartridge. This also could result in pressures rising to an unsafe level. IMO, buy cartridges you know will chamber and cycle properly in your CZ, or, reload your own, that way you can safely tailor them to fit the firearm.

GS

 

[rcmodel]

Short chamber throat + Long bullet ogive = bullet stuck in the rifling when the side drives it home.

You need to stop using that load immediately.

It isn't safe to use in your gun.

Rc

 

[Orion8472]

When I drop a bullet in the barrel [barrel is out of the slide], it seems to drop in without any problem, but then I wasn't giving it the force of "the bolt slamming home on it". I'll check that out more tonight.

I didn't realize that CZ used a short chamber throat. Can you explain how that is dangerous with some cartridges [like the 147gr HST], please? Thanks.

 

[ATLDave]

The throat is the unrifled portion of the barrel forward of the chamber (where we define the chamber to end where the brass ends). Because it has no lands (the raised portion of rifling), it is effectively of larger diameter than the rifled portion of the barrel.

Bullets are sized to fit freely into throats, but not to fit into rifling. The bullet has to be squeezed through the rifled portion under great pressure... that's what causes the rifling to engage the bullet and impart spin. A bullet removed from its case will/should not drop freely through the barrel of the gun it is intended for. It will drop through the chamber and to the end of the throat. At that point, it will be "stuck" in the rifling, and significant force would be required to shove it forward through the barrel.

Longer bullets extend further into the throat. And different shapes/profiles of bullets extend at their full width for different lengths. So if you have a long bullet, or a bullet with a profile that extends its full width a long way, you may find it jamming into the rifling at the end of the throat.

Why is this a problem? Pressure. Guns are pressure-driven. Burning powder generates a huge volume of gas (relative to the volume of powder), and that rapidly expanding gas is what drives the bullet down the barrel. But the first thing that has to happen is that the bullet has to escape the clutches of the brass itself. And that doesn't happen until pressure builds to a certain point. If you have the bullet jammed into the rifling, that point may be well in excess of the pressures your gun was designed to handle. And that's (one reason) why having a bullet jammed into the rifling is no good.

A further, related reason is that the bullet may get "set back" - shoved into the case. Gunpowder generates higher pressures when it is burned in less space. If you jam the bullet backwards into the case, you have just reduced the room that the powder has to burn in, which increases pressures. Again, perhaps above the point that the brass and your gun can withstand.

 

[Orion8472]

Okay, I see what you are saying. I may have to rethink [then] my pistol choices. I prefer the 147gr HST, but if the gun can't safely utilize it, then I may have to go with what will.

 

[Walt Sherrill]

Talk to CZ-USA. Have the chamber/throat adjusted is something they've done for a number of CZ owners, over the years. It was a frequent task for many of the early P-01s. They might let you send the barrel (only) for modification.

You can still shoot the 147 gr. round... (A local gunsmith can adjust the barrel for you, too...)

 

[Orion8472]

I have a gunsmith friend. I'll talk to him about it.

 

[Sam1911]

I've had CZ pistols require a shorter overall length with certain bullet shapes.

IIRC, when I was loading Missouri Bullet Co's "Small Ball" 124 gr. round nose, I had to go to about 1.09" overall before the cartridge would pass the "plunk" test.

Wasn't any big deal, they fired fine. But when unloading the gun I'd have to whack the frame forward pretty hard to pop the bullet out of the leade.

 

[Drail]

Chambering and then re-chambering rounds (especially mass produced factory rounds) is a potentially bad habit to get into. Find a round that fits your chamber and then load a round into the chamber and leave it in the gun. Every time you chamber a round there is a chance for the bullet to be driven deeper into the case. It would be better to leave the gun loaded and lock it away if you have children than to keep unloading and reloading it. If that is not possible consider a revolver.

 

[Orion8472]

Drail, I never like doing that with a striker fired gun. Perhaps it is my own belief that "doing so will compress the spring to where it will fail to return to it's normal uncompressed length".

As for my P-09, I didn't chamber a round in it. I would have only chambered a round if there was that "bump in the night" [which never happened in my apartment anyway].

 

[Armor Snail]

Constant compression doesn't wear springs out. Using them does.

 

[Drail]

That would be the short simple theory. In reality it's a little more complex than that tired old internet mantra. That is what my Physics prof. would call a "gross oversimplification". It would be more accurate to say constant compression is one factor that "may" wear springs out. I have seen plenty of magazine springs die that only sat in loaded guns for long periods without be cycled one time (my own guns and others). Maybe they were made from crap steel, maybe they were loaded beyond their design limits, maybe they were poorly tempered. The fact remains that they still died without any cycling. Orion, leaving your striker spring compressed is not going to weaken it - those springs are almost always loaded far below their design load limit. If it really keeps you up at night buy some quality replacements and replace them once a year. Rechambering rounds daily is still a bad thing unless you load your own ammo and know for a fact they will not set back. It is easy to handload rounds that will withstand multiple chamberings but you won't find that level of control in factory ammo. The manufacturers don't care because they don't expect the customer to do that and they don't warranty the product to be able to do that. Factory ammo is mostly mass produced junk in my opinion. After seeing rounds with loose bullets, no powder, primers inserted upside down and sideways I wouldn't trust any of it for serious business use. Load it once and fire it.

 

[Walt Sherrill]

That would be the short simple theory. In reality it's a little more complex than that tired old internet mantra. That is what my Physics prof. would call a "gross oversimplification". It would be more accurate to say constant compression is one factor that "may" wear springs out. I have seen plenty of magazine springs die that only sat in loaded guns for long periods without be cycled one time (my own guns and others). Maybe they were made from crap steel, maybe they were loaded beyond their design limits, maybe they were poorly tempered. The fact remains that they still died without any cycling.

This topic has been discussed a lot on this forum and The Firing Line. Some of the input has come from engineers working in the business, and from a Metallurgist, and another engineer who has sort of made "spring life" a hobby interest.

Put simply, if the springs are made of quality steel intended for spring applications, and the springs are NOT COMPRESSED TO OR BEYOND THEIR ELASTIC LIMITS, they'll live a long life and likely show only minor loss of performance over that lifetime. Cycling isn't a problem, generally, unless the cycling compresses the springs to or beyond their elastic limits.

Elastic limits? That the point of compression or bending, beyond which things deteriorate. Metal and other flexible materials actually begin to CHANGE when they reach those limits. (Springs designed to stay away from that point last for a long time. Think tappet springs in a car motor, for example.... millions and millions of compressions over an engine's lifetime with few failures.)

Some designers of newer guns ask their mag springs and recoil springs to do more than springs in other guns. (That's necessary when the guns keep getting smaller and smaller, but must perform like bigger guns...)

Keep a slide locked back for long period, when the spring is tightly compressed, and it'll probably not last long.

Keep a mag fully loaded for long periods and the spring might not last a long time -- IF the spring is near it's elastic limit.

(Note: the springs in a 7-round 1911 magazine can be fully loaded for decades without performance degradation. Springs in an 18-round 9mm mag will probably give up the ghost far sooner, if kept fully loaded. Wolff Springs recommends downloading most hi-cap or compact mags a round or two if they're being stored loaded.)

Orion, leaving your striker spring compressed is not going to weaken it - those springs are almost always loaded far below their design load limit. If it really keeps you up at night buy some quality replacements and replace them once a year.

Drail is offering good advice on both points: at least for most striker-fired guns, the striker spring probably isn't FULLY COMPRESSED (i.e., compressed as far as it COULD BE COMPRESSED) even when it's ready to fire.. A smart designer will, unless forced to do otherwise, build in a reserve so that spring life isn't affected. If you're concerned, change them periodically.

 

[Orion8472]

Thanks guys.

But as for the OP topic, . . . I took the barrel out a few moments ago and dropped each of the 147gr HST round into the chamber. Each of them fell right in and did not stick at all. They acted no different than the 115gr FMJ.

But I retried the chambering [after reassembling the gun], and was still getting that stuck slide thing. It almost seems like the round is REALLY held in with the extractor or something else that is binding up the barrel to the slide. Just a guess. I still have no idea what is going on. I'll have to take it by the gunsmith friend.

Updated to add:

This doesn't happen with 124gr Golden Saber or 124gr Hornady Tap, or any other of my 9mm rounds. Was okay with 147gr Golden Sabers. Worked with Critical Defense.

Does not like the 147gr HST, or 147gr Hornady XTP. Did not like a Fiocchi loaded with 115gr XTPHP.

 

[armoredman]

If it won't come out, the force of chambering with the slide is driving the wide ogive into the rifling. Try a round with a narrower profile, like Golden Saber, which works perfectly in my P-09. I personally stay away from 147 grain fodder, personal preference.

 

[Orion8472]

armoredman, what of the fact that dropping a round into the barrel didn't produce any issue of "bullet contacting rifling"? There was no binding when I did this and in fact, the bullet easily came out.

 

[Hurryin' Hoosier]

... driving the wide ogive into the rifling.

Now, that sounds painful!

 

[Orion8472]

As a side note, the 147gr HST rounds work perfectly in my CZ SP-01. Beginning to see how the "older design" may be better than the new direction of CZ.

 

[Orion8472]

Actually, that should have been:

Beginning to see how the "older design" IS better than the new direction of CZ.

I think I'm going to consider selling the P-09 and taking the P--07 off of layaway. Change them out for something different. I want a gun that will cycle the HST round every time.

 

[Walt Sherrill]

You may be getting the cart before the horse...

If you had good reasons for getting a P-07 or P-09 before this misadventure, CZ should be able to make the gun feed your factory round of choice without cost to you.

If you're really not enthused about the P-09/P-07 for other reasons then, by all means...

 

[Orion8472]

Not sure how I can have them duplicate the problem unless they happen to have 147gr Federal HST rounds there. They won't find this issue with 115gr FMJ rounds.

I like the gun and how I have it set up [both magazines have +2 base plates, and I have night sights on it]. However, what's more important is a gun that is reliable with all ammo types.

I've done what I believe to be "the plunk test", and all rounds drop in with absolutely no issue. Not sure why it is getting locked up with this round. . . . . and it isn't all the time either. Some will run through without getting stuck, but the next time I run them through, it will stick up the slide. It's almost as if the round isn't allowing the barrel to unlock from the slide?