Is the barrel on my CZ75B supposed to move?

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jeffesonm

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Okay this might be a stupid question, but I am new to firearms and would rather be safe than sorry :D

I just picked up my first pistol, a CZ 75B. As recommended by some I disassembled it and cleaned it prior to shooting. I followed the manual, took it apart, wiped off all the factory grease, wiped down the barrel, then applied a light coating of gun oil on the parts indicated in the manual. I then put in back together in reverse order, which seemed to go just fine (no leftover parts!)

Now comes the question... when I pull back the slide, I can see the barrel move back maybe 1/8" and drop down about the same amount. When I release it, the barrel moves back to its original position. Is this normal operation?
 
Almost all full size automatics do this. The barrel stays locked to the slide for the first part of it's travel to stop the case from exiting it and rupturing while the pressure is still too high.
 
That's normal and by design. If you look on the underside of the barrel, you'll see a slot that the cross pin of the slide release goes through. When the slide is forward, the cross pin in the slot forces the back of the barrel upward to lock it in place. When the pistol fires, the slide begins moving rearward and the cross pin in the slot forces the barrel down, unlocking it from the slide. The barrel stops while the slide continues traveling back. As the slide again moves forward, the barrel is also being forced to move upward again by the pin in the slot until it's once more locked in place.

That's a very basic description and I didn't mention the recoil spring which plays a part by applying pressure to the barrel as the slide moves rearward.

You can remove the slide and attach the barrel to the frame using the slide release. Then you can move the barrel back and forth to see how the pin in the slot controls the barrel movement.
 
Okay thanks all, that is reassuring that this thing will now blow up in my face when I go try it out.

Just for my own curiousity... why was it designed to operate like this? What is the benefit of having the barrel move, as opposed to having it fixed to the frame or something?
 
That was John Browning's genius. If the breech opens before the pressure drops the case ruptures, and that's very bad! The lockup design makes sure it stays in one piece in your hand. When the pistol locks up for firing the barrel should not move, only during recycling after firing.
 
Just for my own curiousity... why was it designed to operate like this? What is the benefit of having the barrel move, as opposed to having it fixed to the frame or something?
Click to expand...

A locked breech pistol is very strong when compared to a blow-back design that depends upon spring strength and slide mass to control operation. The easiest way to achieve a locked breech is to have the barrel move to unlock and lock again during the cycling of the slide.

When you fire a locked breech pistol, the bullet is long gone and pressure in the barrel has dropped to almost nothing before the slide movement unlocks the barrel from the slide. This fact allows the slide mass and spring pressure to keep things working without battering the parts. It's the compressed spring pressure that drives the slide back to battery, taking a new cartridge from the mag, chambering it and returning the barrel to it's locked position.

The easiest way to achieve a locked breech design is to have the barrel move. Other locked-breech designs include the P-38 and Berretta 92 that use a wedge to lock and unlock the barrel from the slide. Here's a link to the P-38 where you can see and read about it.

Link: http://world.guns.ru/handguns/hg68-e.htm

One design I know of that uses a wedge and a FIXED barrel is the Benelli B-76. It was made in 9mm Luger and .30 Luger (B-78?). But it is still a locked design.

The most powerful straight blow-back pistols that I know of are the Astra 400 and 600. The 400 was chambered in 9mm Largo/.38ACP while the 600 was contracted by the Nazis during WW2 chambered in 9mm Luger. They use a very strong spring and heavy slide to control cycling of the action.
 
hmm, the slide pin is the pivot point, it doesn't make the barrel move
lever and fulcrum - the barrel moves and unlokcs the lugs because the
muzzle end of the barrel is contained by the slide in the horizontal at
that forward end of the slide

It's based on the design that John M. Browning began with the prototype
of the handgun that after his death, his successor at FN in Belgium fnishished and the gun is the pistol first adopted by the Belgium army the
Pistole P35, aka Browning High Power. It was the first to incroporate a
stacked high capacity magazine - John browning didn't think the high
cap magazine was needed but it was a requirement by the french. The
french ended up bailing on the FN design and went with a pistol designed
by an engineer named Peders., the MAB35 which the SIg p210 and the
later CZ 75 have in commong the slide that has the rails inside the frame
unlike most slides which are like the 1911. Browning was forced to design
the Browning Hi-Power around the patents Colt had where the barrel has a
link as part of the pivot/unlocking of the barrel & Slide.

Randall - just stirring things up
 
hmm, the slide pin is the pivot point, it doesn't make the barrel move
Click to expand...

Hummmmmm.... without the pin, what would force the back of the barrel out of battery? When the back of the barrel is forced down by the pin, that's movement. What I think you mean to say is that the pin isn't the cause for the barrel to initially move rearward with the slide. I agree.

the barrel moves and unlokcs the lugs because the
muzzle end of the barrel is contained by the slide in the horizontal at
that forward end of the slide
Click to expand...

Movement of the slide holds the barrel in the locked position until the pin, riding in the barrel's slot, forces the back of barrel downward, unlocking it, because the slot is angled to do exactly that. It's the pin in the slot that keeps the barrel at the correct angle from lock-up through ejection, chambering a new round and locking up yet again.

The bushing serves as a guide for the barrel and the barrel is free to move in the bushing. Movement of the barrel in and out of battery is controlled by the slide and the slide release pin that rides in the barrel slot.
 
Hmm

The most powerful straight blow-back pistols that I know of are the Astra 400 and 600. The 400 was chambered in 9mm Largo/.38ACP while the 600 was contracted by the Nazis during WW2 chambered in 9mm Luger. They use a very strong spring and heavy slide to control cycling of the action.
Click to expand...
FWIW, I think Hipoint makes a 45 acp.
 
Three basic designs:

Recoil operated - 1911, Hi-power, etc.
Blowback operated - Hi point, Bersa 380, some small Berettas, some Astras, etc.
Blow-up operated - Glock :p

I'm sorry, I couldn't help myself. (I own Glocks)
 
FWIW, I think Hipoint makes a 45 acp.
Click to expand...

Thanks. I wasn't aware of HiPoint's pistol. Truthfully, I stopped trying to keep up with all the new models some years ago. Plastic pistols do absolutely nothing for me.

Schmeky, that's very funny! :D
 
Okay thanks all, that is reassuring that this thing will now blow up in my face when I go try it out.
Click to expand...
CZ's are VERY durable guns.
On a side note, you may want to read up some more before you go shooting that thing, you know, to make sure you know where to put the bullets :p
 
Hey Jeffesonm,

Congrats on your new CZ! Mine came with a LOT of grease. Great for storing the gun before it reaches its new owner, but it's way too messy to shoot that way. Glad you cleaned it!That much lube attracts and holds dirt. You might want to consider re-cleaning it with Gun Scrubber and a light lube with Break Free before you shoot it the first time.

Be sure you don't over-lube! These guns work with a very, very light lube on them. Avoid putting significant lube on the "bolt face" part of the slide, where the firing pin would contact the back of the round while in the chamber. This lube would get into your primers if you store the gun locked and decocked for ready use, and possibly cause a failure to fire. On most parts, wiping off the lube with a cloth will leave enough to inhibit corrosion and provide friction reduction, without leaving a sticky, oily layer that will attract dirt.

When you shoot it, be sure to hold the gun firmly to resist the recoil. If you do NOT do so, the whole gun will move backwards, robbing the slide of a full stroke. The result will be a failure to eject or feed... If this happens to you, you might be holding the gun a little too loosely. First time my wife shot the Glock 9mm, that's what happened to her. I had just shot off 30 rds without a problem, so I knew there was nothing wrong with the gun.

Good luck, be safe, and enjoy!
 
Thanks all for the help.

I probably should have clarified a bit... this is my first pistol, but I already own a shotgun (skeet shooting) and have fired many various pistols over the years with friends and family. Figured it was finally time to get one of my own. Also have a Browning Buckmark on the way as well as a Tokarev.

And yes CP, I definitely meant "will not blow up in my face" :D
 
Kudos to doub43 for clarification except for one
glaring error, like the BHP, the CZ 75B doesn't have a barrel bushing

and Scheky thanks for the LOL about the Glock Ops

Jefferson, I have a CZ 75B - got it a year ago, and except for a
couple of boxes of recent purchase, CCI Blazer with aluminum cases
that produced a hafl dozen stovepipes per box it has been flawless
in operation. As another said, get the shipping grease off the
gun, - as well as the inside of the slide and rails using Hoppes #9
give it a lube and reassemble. go to the range and enjoy.
Note:
* when inserting a magazine give it a good smack with the
heel of your off hand,
* when operating the slide manually since the slide sits inside the
frame I find the best way to grasp it is to use the LH thum and index
finger on the rear slide serrations.

* Removing a magazine, unlike most domestic semi-autos and most
foreign made semi-autos when you hit the magazine release instead
of the magazine falling out, the magazine will only drop maybe a
half inch. The magazine is retarded from movement by a bent piece that
sits in the rear of the grip/frame. It can be bent - check
instructions on the CZForum or you can get a replacment part
that doesn't retard the mag. - it's standard on the 75 they
build for competition. I haven't changed mine since it's just my
econo range gun - I got it to shoot 9mm luger and cut back on
the number of .45 ACP I throw down range with my 1911 and
625 revolver.

Randall
 
Kudos to doub43 for clarification except for one
glaring error, like the BHP, the CZ 75B doesn't have a barrel bushing
Click to expand...

Technically, you are correct by most definitions. However, while it's permanent and can't be removed, it is, for all intents and purposes, a bushing. It serves the same purpose as a true bushing so what else would it be called?
 
I don't know if this has been mentioned, but the barrel drops down to also improve feeding reliability as the ramp will line up with the feed lips on the magazine.
 
doug43 your stretching the def. of a bushing, or being an english major
Click to expand...

And you, Sir, are reading and spelling challenged. You should have written: doubs43, you're stretching the definition of a bushing, or being an English major.

So educate me and tell me what YOU call the opening in the front of a pistol slide through which the barrel protrudes. Surely one who knows what it isn't will know what it is.
 
For the sake of this thread, and the O.P.

THe 1911 design has a bushing it in the slide to barel connection.
as well as a barrel link

The Browning High Power and CZ 75B does not have the
bushing nor the link.

Both designed by John M Broning

Both designs are different but they are a delayed unlocking of the
slide to barrel with the lugs, male/female.

The same function engineering wise can be accomplished by
different components.

An example in an engine is most engines have have valve springs to control
the opening and closing of the Intake and exhaust valves. In a dsmodromic
valve acutation system there are no valve springs - there is a rocker arm than physically opens and closes the valves. WIth doubS43's logic that
control arm would be termed a Spring - but no spring is present in the dsemo design.

Yeah I get in a hurry typing, doubs43 hey, I don't spellcheck - it's a bit tedious I'm legally blind so that's the explanation of my handle on
this forum. No need to call me sir, I was never commissioned as an officer
although I got close in OCS Took a different path.

Have a good saturday, I'm going to the range - I can still hit the
silhouette target at 7-10 yards with my 1911 or CZ 75B - hey yah know
what - in the manual for the CZ 75B it never says anything about removing
a bushing in take down.

Randall
 
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