Czechmate barrel failed

[yigal]

6 hours ago, gianmarko said:

 looks like the barrels need exactly that type of fitting

 

there is quite a lot of metal to be removed from the rear barrel face

 

0.1mm    it's not a lot.

 

[gianmarko]

14 hours ago, yigal said:

 

0.1mm    it's not a lot.

 

is probably over 0.5 in my case, ok is not "a lot" but not something i can remove with 2 licks of file :-)

 

[yigal]

2 hours ago, gianmarko said:

is probably over 0.5 in my case, ok is not "a lot" but not something i can remove with 2 licks of file :-)

 

 

over 0.5mm  is too much . it should be less.cz original  barrel came in  quiet  accurate dimension for minimal fitting job.

but good to know.

don't forget chamfer the edge 0.5x45*  if not  it will not have full lockup .

[gianmarko]

On 6/24/2017 at 2:49 AM, abb1 said:

3 hours ago, yigal said:

 

over 0.5mm  is too much . it should be less.cz original  barrel came in  quiet  accurate dimension for minimal fitting job.

but good to know.

don't forget chamfer the edge 0.5x45*  if not  it will not have full lockup .

 

 

Yigal

your informations are really very appreciated, thanks a lot.

 

ill look into fitting one barrel after xmas holidays. ill try to make more accurate measurements and update on progress

 

gm

 

 

[my00wrx1]

On 16/12/2017 at 9:50 PM, yigal said:

 

over 0.5mm  is too much . it should be less.cz original  barrel came in  quiet  accurate dimension for minimal fitting job.

but good to know.

don't forget chamfer the edge 0.5x45*  if not  it will not have full lockup .

Which edge needs to be chamfered?

[Matt1]

I can’t remember if I’ve posted in this thread before.

I’ve been shooting various CZ’s for 5 years now and have cracked one barrel (in my CM, after about 10k rounds) and one slide stop (again in the CM, at something less than 10k rounds).

My gun is the same vintage as MY00’s. I didn’t bother chasing a warranty replacement even though I heard that he did. The local CZ importer is a friend of mine and looks after me well enough. If I ever have to buy another barrel the $200 won’t break the bank.

I’m currently loading Autocomp to 170PF. I’ve always run a 14lb recoil spring but no buffer.

Interestingly I have something like 30k rounds through a TSO in .357 Sig at 185PF. 18lb spring, no buff, similar barrel design. No issues so far.


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[yigal]

3 hours ago, my00wrx1 said:

Which edge needs to be chamfered?

top area around outer diameter    of the chamber  and sides. like on this pic.

[gianmarko]

1 hour ago, Matt1 said:

I can’t remember if I’ve posted in this thread before.

I’ve been shooting various CZ’s for 5 years now and have cracked one barrel (in my CM, after about 10k rounds) and one slide stop (again in the CM, at something less than 10k rounds).

My gun is the same vintage as MY00’s. I didn’t bother chasing a warranty replacement even though I heard that he did. The local CZ importer is a friend of mine and looks after me well enough. If I ever have to buy another barrel the $200 won’t break the bank.

I’m currently loading Autocomp to 170PF. I’ve always run a 14lb recoil spring but no buffer.

Interestingly I have something like 30k rounds through a TSO in .357 Sig at 185PF. 18lb spring, no buff, similar barrel design. No issues so far.


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Hi Matt

i have a CM barrel with some 30k rounds and no issues so far. i know a guy with a 2013 CM and over 50k rounds on the same barrel no issues

the barrel i broke was probably less than 7k rounds.

it doesnt seem to be a regular occurrence like the slide stops.

 

by the way, another shooter i know claims that at 12k rounds her barrels lose precision and need replacing. never heard such thing before. i havent noticed any loss of precision in my CM,

 

 

 

 

[yigal]

7 minutes ago, gianmarko said:

Hi Matt

i have a CM barrel with some 30k rounds and no issues so far. i know a guy with a 2013 CM and over 50k rounds on the same barrel no issues

the barrel i broke was probably less than 7k rounds.

it doesnt seem to be a regular occurrence like the slide stops.

 

by the way, another shooter i know claims that at 12k rounds her barrels lose precision and need replacing. never heard such thing before. i havent noticed any loss of precision in my CM,

 

 

 

 

it firearm that works .everything could happen.

i used cz75 as open gun with peter sthal  barrel .it still made good groups at 25 m. even only 1" of rifling  stay alive.

but this issue  need to be checked. 

[gianmarko]

in the meanwhile i got some of those impact wrench pins. they are tough, i tried to machine one to shorten it a little and it vaporized the chisel insert

 

i shot a match with it yesterday, looks good, no problem so far. if it solves the slide stop problem, ill get a beer or two to the guy who found this out.

 

 

[gianmarko]

broken barrel n.2

this one belongs to another CM i bought second hand from a colleague

he only shot factory ammo and was lightly used. so much so that he was still using the original slide stop/hold open

barrel is marked 2015

 

i shot perhaps 5000 rds on this gun, around 165PF

 

this barrel looks identical to the one that failed in my CM n.1,  that was manufactured in 2013

 

the second barrel from top is a new barrel from my CM n.1, manufactured in 2013

 

the third barrel from top is the new 2017 barrel. the lug, in the area that fails, is 0.5 mm thicker, and profiled slightly differently

 

now my doubt is whether the failure was caused or accelerated by the handmade slide stop pin im using. it is 0.04mm thicker than the CZ slide stop, and it looks like it mates the cam in the lug even better than the stock CZ pin

 

 

 

 

 

 

 

[gianmarko]

aaaand

more problems

 

i have installed one of the two spare barrels and i get this gap between comp and slide

 

looks like they forgot a thread, there is exactly 1 mm gap. wtf? both spare barrels show this problem

 

i counted the threads and they are 24 on all barrels. so not sure i should put the barrel in the lathe and add one thread or what.

 

and btw, anybody knows the difference between A and B serial number guns?

 

 

 

 

 

 

Edited February 7, 2018 by gianmarko

[adamge]

I wouldn't blame your slide stop.  All of those generation 1 barrels fail in the 3-15k round count range. Guaranteed to fail.

 

And your comp threading, are you sure you ran out of threads?  Or is it just that the comp hits the slide if you go another turn?  One CM I know where, when it had to replace the barrel, on the new barrel if you went enough turns to get a tight comp-slide gap, it was too tight and wouldn't go into battery.  That CM was ran with comp one turn out for about 1k rounds, at which point the comp would go on one more turn and is now a good tight gap.  It was never out of threads.

[gianmarko]

1 hour ago, adamge said:

I wouldn't blame your slide stop.  All of those generation 1 barrels fail in the 3-15k round count range. Guaranteed to fail.

 

And your comp threading, are you sure you ran out of threads?  Or is it just that the comp hits the slide if you go another turn?  One CM I know where, when it had to replace the barrel, on the new barrel if you went enough turns to get a tight comp-slide gap, it was too tight and wouldn't go into battery.  That CM was ran with comp one turn out for about 1k rounds, at which point the comp would go on one more turn and is now a good tight gap.  It was never out of threads.

 

actually on the CM n.1 the barrel n.2 is now at perhaps 30 or 35k rounds and still going. i know a guy who is at 50k and still going.

 

no, i thread the comp with the barrel not in battery and the spring out, and cant turn it any further. something is hitting the end of something else. either the thread or the barrel into the comp.

 

i have measured and looked  with a microscope at the different barrels. threads are absolutely identical and so are sizes, i suspect the comp hits the barrel muzzle and bottoms, the only difference i could find is that the broken barrell has a small chamfering at the muzzle. later will put some marker on the new barrel and see where it bottoms.

[gianmarko]

so i chamfered a tiny amount  the outside of the barrel muzzle and now the comp threads to the end

 

but the troubles continue

turns up when the comp is completely screwed in, the barrel-comp assembly is some 0.1mm too short so the barrel doesnt sit completely in the slide , and the slide drags in the first cm of travel when racking. with one of the two spare barrels is worse and the gun will not close on the force of the spring alone.

 

 

so if the comp is installed like it in the picture, with the 1 mm gap between slide and comp, the gun works fine, albeit there is a little play at the coupling slide-comp

if i screw it in one more turn the barrel remain a tiny amount unseated towards the slide and the whole thing drags. in fact, i always noticed this drag in this pistol when racking the slide, but was minimal

 

so i either live the 1mm gap and leave the comp unscrewed by 1 turn, or i need to remove some 0.15mm either from the front face of the slide or the rear face if the comp

 

the guy who adjusted the pistol in the factory did a pretty sloppy job. the CM n.1 doesnt show any of these and everything works fine, no matter which barrel i fit.

 

the CM n.1 shows a gap of 0.15mm between slide and comp

 

 

any opinion?

thanks

 

 

[yigal]

19 minutes ago, gianmarko said:

so i chamfered a tiny amount  the outside of the barrel muzzle and now the comp threads to the end

 

but the troubles continue

turns up when the comp is completely screwed in, the barrel-comp assembly is some 0.1mm too short so the barrel doesnt sit completely in the slide , and the slide drags in the first cm of travel when racking. with one of the two spare barrels is worse and the gun will not close on the force of the spring alone.

 

 

so if the comp is installed like it in the picture, with the 1 mm gap between slide and comp, the gun works fine, albeit there is a little play at the coupling slide-comp

if i screw it in one more turn the barrel remain a tiny amount unseated towards the slide and the whole thing drags. in fact, i always noticed this drag in this pistol when racking the slide, but was minimal

 

so i either live the 1mm gap and leave the comp unscrewed by 1 turn, or i need to remove some 0.15mm either from the front face of the slide or the rear face if the comp

 

the guy who adjusted the pistol in the factory did a pretty sloppy job. the CM n.1 doesnt show any of these and everything works fine, no matter which barrel i fit.

 

the CM n.1 shows a gap of 0.15mm between slide and comp

 

 

any opinion?

thanks

 

 

i think that remove 0.15mm from comp. is better way than from the slide.

and about cz factory custom gun sloppy job  it's their trade mark  

say thank god that u have ANGUS .H.

[gianmarko]

lol well the CM n.1 is very well adjusted

 

then is time to get the 4 jaws chuck out, i cannot be trusted handling a file

 

 

[yigal]

32 minutes ago, gianmarko said:

lol well the CM n.1 is very well adjusted

 

then is time to get the 4 jaws chuck out, i cannot be trusted handling a file

 

 

i can give u mine 4"  4 jaws chuck  i don't use it.

i made jigs for that type works for 3j.c.

Edited February 8, 2018 by yigal

[gianmarko]

ok i have machined 0.3mm off the back face of the comp and now it fits perfectly.

 

man, these guns are funny. there is 0.5mm difference in lenght between the slides of the two CM. i suspect in the factory they machine the slide, not the comp, to mate them

 

 

 

 

[yigal]

2 hours ago, gianmarko said:

ok i have machined 0.3mm off the back face of the comp and now it fits perfectly.

 

man, these guns are funny. there is 0.5mm difference in lenght between the slides of the two CM. i suspect in the factory they machine the slide, not the comp, to mate them

 

 

 

 

i have 2 tso both of them seats in hand different .

i measured grip frame and find that it not the same.  1.5mm  difference in beaver tail cut depth .

[abb1]

On 2/7/2018 at 6:01 AM, gianmarko said:

 

 

and btw, anybody knows the difference between A and B serial number guns?

 

 

 

 

 

 

 

I would say that Serial #'s are by revision. A is the first revision whereas B is the second revision. My CM is about 2 1/2 years old and B revision. It has a beefed up barrel, and it has about 15-17K rds through it. The gun only came with ONE barrel. No issues what so ever, and still going strong.

Edited February 9, 2018 by abb1

[yigal]

cz claim that their shooter shot 150k with his cm. 

so what is the problem ? u can add few 00  too.

 

 also contains two spare barrels, although it is questionable whether they would ever be used. It is known that the top Česká zbrojovka shooter Martin Kameníček, who participated in the development of this model, fired more than 150 000 rounds over five years from his CZ 75 TS CZECHMATE and only had to replace the barrel once, since after such a trial, its accuracy did start to decrease.

[gianmarko]

i suspect MK pistol was not exactly the same that they sell to us commoners

 

at any rate i am not complaining, the gun shoots very well, and its on average a lot more reliable than many other expensive pistols i see in the hands of colleagues.

 

at the mo the CM its sold at 3.8k swiss francs including ther spare barrels, and i see other people forking out close to 6 for other guns that then require another 1k of gunsmithing in order to run reliably

Edited February 9, 2018 by gianmarko

[abb1]

To my knowledge spare barrels were included with the first revisions. When they offered their ‘beefed’ up barrel, they only provided the one. I have never heard of a beefed up barrels failing and this is obviously what the CZ team are shooting. I can’t see them shooting 150k rnds out of a first revision barrel. 

[yigal]

1 hour ago, gianmarko said:

i suspect MK pistol was not exactly the same that they sell to us commoners

 

at any rate i am not complaining, the gun shoots very well, and its on average a lot more reliable than many other expensive pistols i see in the hands of colleagues.

 

at the mo the CM its sold at 3.8k swiss francs including ther spare barrels, and i see other people forking out close to 6 for other guns that then require another 1k of gunsmithing in order to run reliably

don't suspect.

it's not the same. but still it is very good gun.

 and i suspect that from better metal and not from recycled scoda that they made them for us.

 

Edited February 9, 2018 by yigal