The Original CZ Forum

CZ PISTOL CLUBS => CZ75, 75b, 75 SAO - All Full-Size Pistols => Topic started by: Metal Wonder Nine Guy on September 04, 2019, 10:58:42 PM

Title: Weak design points of the CZ-75
Post by: Metal Wonder Nine Guy on September 04, 2019, 10:58:42 PM
For the record, I am not trying to start an argument over which design is best. Every pistol have some sort of weak part that eventually breaks. For instance, the Beretta 92's locking block can eventually crack, and Glocks sometimes break trigger springs and locking block pins.

What parts can break on the CZ-75? From what I've read so far, the slide lock can eventually break from overuse if the slide lock is used to release the slide home. Like any other semiauto pistol, the recoil springs need to be changed at certain intervals. Any other flaws I should know about?
Title: Re: Weak design points of the CZ-75
Post by: SI VIS PACEM PARRABELLUM on September 05, 2019, 04:52:37 AM
The act of firing the weapon puts far more stress on the slide stop than using it to release the slide. The slide stop can break after thousands of rounds and trigger springs have been known to break. The firing pin retaining pin is a wear item especially if you a chronic dry firer.
I've never broken either in any of my CZ's.My 75BD has fired over 24,000 rounds now with nothing more than recoil spring changes at regular intervals.
Title: Re: Weak design points of the CZ-75
Post by: eastman on September 05, 2019, 10:34:51 PM
The slide stop takes a lot of abuse during firing and is designed as a sacrificial part. Much better to replace a broken $35 slide stop than a $150-200 barrel.
Title: Re: Weak design points of the CZ-75
Post by: Metal Wonder Nine Guy on September 06, 2019, 02:19:12 PM
The slide stop takes a lot of abuse during firing and is designed as a sacrificial part. Much better to replace a broken $35 slide stop than a $150-200 barrel.
That's  pretty much the same idea with the locking block on the Beretta 92 pistols. And locking blocks also cost 35 bucks too.
Title: Re: Weak design points of the CZ-75
Post by: SI VIS PACEM PARRABELLUM on September 06, 2019, 04:45:45 PM
The beretta locking blocks were revised many moons ago an hold up pretty well now.
Title: Re: Weak design points of the CZ-75
Post by: briang2ad on September 06, 2019, 05:29:05 PM
Some people go pretty far with the slide stop.

 The poorest feature by far on the CZ 75 system both on the 75 and the P series is the trigger return spring. It is a very poor design. It will break within 5000 firings of the weapon.  I have forced them to break dry firing them with less than 1000 rounds through them.  Even cajun gun works admits that the design is a flaw.  I can dry fire the snot out of my Sigg‘s and other guns and not worry about it. However, the CZ trigger return spring is just a bad design and it’s not about the metallurgy.
Title: Re: Weak design points of the CZ-75
Post by: ejb1975 on September 06, 2019, 06:00:39 PM
Some people go pretty far with the slide stop.

 The poorest feature by far on the CZ 75 system both on the 75 and the P series is the trigger return spring. It is a very poor design. It will break within 5000 firings of the weapon.  I have forced them to break dry firing them with less than 1000 rounds through them.  Even cajun gun works admits that the design is a flaw.  I can dry fire the snot out of my Sigg‘s and other guns and not worry about it. However, the CZ trigger return spring is just a bad design and it’s not about the metallurgy.
Do you do a full DA pull every time you pull the trigger when you dry fire? My Cajun TRS’s hold up quite well, I do replace every spring in the gun once a year on my comp gun though. 


Sent from my iPhone using Tapatalk
Title: Re: Weak design points of the CZ-75
Post by: SI VIS PACEM PARRABELLUM on September 06, 2019, 06:41:23 PM
Some people go pretty far with the slide stop.

 The poorest feature by far on the CZ 75 system both on the 75 and the P series is the trigger return spring. It is a very poor design. It will break within 5000 firings of the weapon.  I have forced them to break dry firing them with less than 1000 rounds through them.  Even cajun gun works admits that the design is a flaw.  I can dry fire the snot out of my Sigg‘s and other guns and not worry about it. However, the CZ trigger return spring is just a bad design and it’s not about the metallurgy.
Do you do a full DA pull every time you pull the trigger when you dry fire? My Cajun TRS’s hold up quite well, I do replace every spring in the gun once a year on my comp gun though. 


Sent from my iPhone using Tapatalk
He's broken alot of CZ trs according to him but I'm the minority as I've never broken a CZ trs.Mine are just plain better than his metallurgically and otherwise.Joking aside Beretta 92 series will break the trs and glocks will to. Guns are machines and need maintenance at times  and that is a very simple mechanical fact that anyone should be able to understand.
Many of these modern era mini pistols that everyone loves so  much require very routine recoil spring replacement to maintain reliability due to their small stature.
Bottom line is take care of the machine and it will take care of you.
Title: Re: Weak design points of the CZ-75
Post by: briang2ad on September 07, 2019, 08:23:44 AM
One year I broke seven or eight and stopped counting. A lot of my dry firing had to do with repeated double action dry fires. I did that so that I could smooth out the trigger which can be very gritty and CZ 75s.   I think this heats up the trigger return spring and weakens the metal.  I never really thought it had to do with a design flaw itself until I talked to cajun gun Works and they identified it as a flaw.    There are likely other designs that break trigger return springs so maybe CZ is not the only one.  CZ has developed a new spring that may be more substantial but it is also heavier. Cajun offers one that is lighter and does fairly well. If I were using a weapon as for self-defense I would not have a stock spring in it from the past.
Title: Re: Weak design points of the CZ-75
Post by: tde44 on September 07, 2019, 10:48:10 AM
Too many really small parts & pins for an older guy with fat fingers...especially the sear cage.

Although I still enjoy them and won't give them up.
Title: Re: Weak design points of the CZ-75
Post by: Joe L on September 07, 2019, 11:41:10 AM
I have only had one failed trigger return spring.  I replaced it with a CGW spring and haven't replaced it in maybe 40k rounds.  Note my pistol is single action only with minimum trigger movement, essentially no dry fire, and no rapid fire, so my usage is probably the least demanding of most users.  I have never broken a slide stop, but I shoot the Kadet and not so much the 9mm slide.  I did replace the original slide stop when I replaced the trigger return spring.  My point is that these aren't chronic maintenance issues.  I can imagine that a high volume double action/single action 9mm or 40 cal 75B would bring out more weaknesses than I have experienced.  If I were really diligent, I might replace these parts every 2 years or maybe 20k rounds anyway, just to avoid any issues during a match. 
Title: Re: Weak design points of the CZ-75
Post by: Claymore504 on September 10, 2019, 08:02:33 AM
I would say the items to pay attention to on CZs have been mentioned. Firing pin retaining pin can be damaged very easily and that would be number 1 to me. When I first got into CZ handguns my first one was a SP-01 Tac 9mm. I dry fired it maybe 30-50 times. Then I started reading about dry fire and FPRP damage. I ordered a CGW pin and removed the old one to replace it. Sure enough it was severely damaged.

So, snap caps and/or oring for dry fire for me after that. Then I would put the TRS next. Keep it lubed and replace depending on your use. The the slide lock. Those seem to make it for thousands of rounds, so I would put that lowest on priority.
Title: Re: Weak design points of the CZ-75
Post by: Walt Sherrill on September 10, 2019, 10:22:12 AM
Quote from: briang2ad
...I think this heats up the trigger return spring and weakens the metal.  I never really thought it had to do with a design flaw itself until I talked to cajun gun Works and they identified it as a flaw. 

Trigger Return Spring: It MAY be a metallurgical issue if the CGW springs last longer, and some seem to think they do. 

That said, I'd be very surprised if the heat from working the spring by FIRING the gun  would have as much effect on the metal in that spring as the heat generated by simply firing gun rapidly.  You'd really have to get that spring very hot before the HEAT would begin to degrade the spring material, and IF pulling the trigger generated that much heat, I suspect some of that heat would transfer to the trigger itself and be noticed.  I don't think it is. 

Firing Pin Retention Roll Pin Breakage: It may be that just lengthening the cutaway area on the top of the firing pin,    the ends of which stop the roll pin, could be a solution, or a different  spring design (maybe a variable rate spring, or simply a lighter spring).    The firing pin retention roll pin [FPRRP]is there to keep the firing pin IN the gun, when the hammer is NOT* down or at the half-cock position,  and there may be a better way to do that -- like the firing pin stop plate that was replaced by the FPRRP.)

(*I mistakenly omitted the NOT the first time through.  That wasn't what I meant!!  I edit too much.  I wonder, too, if a larger diameter FRRPR -- maybe a solid one -- positioned a bit higher in the slide make take the abuse a bit better?  That wouldn't help with existing guns, but it could make it a non-issue when newer models.)
Other Design Issues not Addressed: the fact that CZ hasn't bothered to incorporate design changes that will allow a shorter  length of trigger pull -- something that CZ CUSTOM and Cajun Gun Works did years ago.  CZ could also improve their sights a bit without changing production costs much (if at all.)  I've never heard ANYONE say anything nice about the standard CZ sights.

Production Short Cuts: The fact that many other guns come out of the factory with better triggers is a competitive feature that works against CZ.  Or that the SA hammer often cams noticeably (moves to the rear before dropping), when released, delaying and degrading what could be a great SA trigger.  We know that the competition's hammers address this and basically avoids that trait.  Some have argued that this was a corporate decision, influenced by lawyers who want to reduce potential corporate liability, but that simply doesn't make sense.  A clean SA trigger doesn't increase liability -- if it did any number of 1911 custom gun makers would have been put of business long ago.
Title: Re: Weak design points of the CZ-75
Post by: briang2ad on September 11, 2019, 07:16:20 AM
Quote
That said, I'd be very surprised if the heat from working the spring by FIRING the gun  would have as much effect on the metal in that spring as the heat generated by simply firing gun rapidly. 

As usual good analysis from Walt. 

I would tend to agree.  When I have dry fired some of my CZs I went bonkers trying to smooth the trigger, so heat may have become an issue.  Still, I've had them break in less than 1000 dry fires and wet fires.  I think CGW is right - it is an inferior design compared to other designs. 

Which gets to another issue - QC.  I've picked up P guns with triggers that need very little other than firing a half case of ammo.  I've had others that needed parts changes and all types of polishing.  Yes, they needed it.  I even have a preB that needed a trigger bar change to 'get right.'

Your comments on sights and hammer are SPOT ON. 

Title: Re: Weak design points of the CZ-75
Post by: Walt Sherrill on September 11, 2019, 09:49:27 AM
Some years back I traded into a Witness Sport Long Slide which was an early precursor to the Witness Match.  Mine was a very nice .45.  When tearing it down it was obvious that the trigger bar was a big offender in that trigger situation.  I dry-fired it for hundreds of times a night for weeks, and it improved.  But it wasn't until I took it out and sanded and polished it, that it really gave me a good trigger. 

And then  the trigger bar broke.  I repeated the process, without the dry-fires and quite so much sanding, and it was very good.  I later traded it away.   I think I was "snake bit" by that gun.  That same gun ate its own barrel (cracked through the chamber area using factory ammo, and the the Super  Sight broke -- and there are NO replacements EXCEPT another Super Sight (from Tanfoglio) available.  Very unique rear dove tail.   That sight was $100+ about 20 years ago, and I'd hate to think what one would cost today, if you can get one.

Polishing the hammer strut is something that some folks suggest, and I think that makes great sense.  (I have a heavy-triggered Lionheart LH9 that I might try that On, as I can't find a good replacement hammer spring.)

Another gunsmith even recommended polishing the inside walls of the hammer spring (but didn't explain how to do THAT -- maybe a  long round chainsaw file?)   
Title: Re: Weak design points of the CZ-75
Post by: briang2ad on September 11, 2019, 12:12:15 PM
I do think the hammer/trigger "camming" issue is about mindset.  The Czechs were squarely part of the Eastern Bloc then , and despite their Western history were clearly not part of a 'consumer mindset'.  Producing a gun that kept its military export customers from Negligent discharges was more important than other aspects, so producing a hammer/sear that cammed before break was preferred.  I don't think anyone East of Germany was worried about lawyers back then.

While I normally polish hammer struts I've not found it to be of noticeable benefit. 
Title: Re: Weak design points of the CZ-75
Post by: Walt Sherrill on September 11, 2019, 03:21:24 PM
Quote from: briang2ad
I do think the hammer/trigger "camming" issue is about mindset.  The Czechs were squarely part of the Eastern Bloc then , and despite their Western history were clearly not part of a 'consumer mindset'.  Producing a gun that kept its military export customers from Negligent discharges was more important than other aspects, so producing a hammer/sear that cammed before break was preferred.  I don't think anyone East of Germany was worried about lawyers back then.

While I normally polish hammer struts I've not found it to be of noticeable benefit.

I don't think the CZ-75 was ever intended to be a military weapon. I think the CZ-75 was designed with the Western civilian market in mind (or if NOT the Western civilian market,  non-NATO states elsewhere in the world.)  Maybe something in the reference  or CZ history books will show that I've misunderstood what really happened.

Why?  No other weapons in the Warsaw Pact arsenal used the 9x19 round. (One exception I know of was the captured Lugers used by the East German  Police, but that was a special case.  I had one of those!!)

I think it d it would have been a cold day in hell before any Western/NATO military bought military weapons from a Warsaw Pact member country during the Cold War.   (And let us not forget that there was a Western TRADE EMBARGO against the communist bloc that had started in 1949 and lasted for about 50 years!  Canada was one of the few Western countries where you could get a CZ-75!)

Had military use been a goal, CZ could've created a number of variants in other calibers that might have been used in the Warsaw Pact.  A CZ-75 in 7.62x25 -- which would require a bit bigger grip -- might've been interesting.  I'd take one of those over a CZ-52 or Tok-33 any day!)

The "camming" wasn't really all that noticeable in the pre-Bs or early 75B models, and it doesn't go away by itself or after break-in. The "camming" in new guns seemed to get worse in recent years, but it seems to come  and go.  I don't  know, but suspect that that CAMMING isn't an issue for the larger IPSC/USPSA guns from CZ; I heat little but praise about those actions.
Title: Re: Weak design points of the CZ-75
Post by: briang2ad on September 12, 2019, 07:55:03 PM
Walt:  I still think it was an Eastern Bloc mindset and it was deemed 'safer', and simpler to make.  My 84 PreB cams plenty.  Maybe the early Prebs did not as much - never held a first model.
Title: Re: Weak design points of the CZ-75
Post by: Tok36 on September 12, 2019, 09:03:11 PM
Another gunsmith even recommended polishing the inside walls of the hammer spring (but didn't explain how to do THAT -- maybe a  long round chainsaw file?)

SP01SHADOW
(Past forum member) covered this in one of his posts a while back ill see if i can track it down. I have not attempted it my self, polishing the hammer strut has been sufficient with my CZ projects thus far.

Edit:
Reply #97 of this thread.

CZ 75 BD COMPACT BUILD

https://czfirearms.us/index.php?topic=89226.90
Title: Re: Weak design points of the CZ-75
Post by: Earl Keese on September 12, 2019, 09:26:36 PM
"Another gunsmith even recommended polishing the inside walls of the hammer spring (but didn't explain how to do THAT -- maybe a  long round chainsaw file?)"

I just tightly roll a piece of sandpaper. Oil it up, feed it through and start shoe shining. Not sure if it's worth the effort, but it doesn't take very long so I do it if I'm being thorough.
Title: Re: Weak design points of the CZ-75
Post by: briang2ad on September 23, 2019, 08:46:05 PM
https://czfirearms.us/index.php?topic=106464.0

Yup.
Title: Re: Weak design points of the CZ-75
Post by: Indy_Tim on September 25, 2019, 05:56:53 AM
"Another gunsmith even recommended polishing the inside walls of the hammer spring (but didn't explain how to do THAT -- maybe a  long round chainsaw file?)"

I just tightly roll a piece of sandpaper. Oil it up, feed it through and start shoe shining. Not sure if it's worth the effort, but it doesn't take very long so I do it if I'm being thorough.

Another method might be to pull a bit of paracord through the spring and then put some polishing compound on it while working it back and forth.  I’m not sure how much of a difference that could make but I may give it a shot on one of my 75s.
Title: Re: Weak design points of the CZ-75
Post by: briang2ad on September 25, 2019, 12:35:00 PM
I've polished plenty of hammer springs/struts in CZs ans SIGs.  It NEVER makes an appreciable difference. 
Title: Re: Weak design points of the CZ-75
Post by: chenjeffus on September 28, 2019, 08:46:18 PM
I have heard lots of about weak trigger return spring on CZ.  Not until last week, I had one break on my Shadow 2.  $7 for the spring and $13 for the pin, took about 20 mins to replace..