The Original CZ Forum
CZ PISTOL CLUBS => CLUB CZ97 => Topic started by: ZenShooter on June 11, 2018, 04:50:46 AM
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Hi,
recently (of course) during a competition a cartridge produced a strange jam. The bullet seemed to crash into the bottom edge of the feed ramp.
(https://i.imgur.com/NZRmUoE.jpg)
(https://i.imgur.com/2L8uIEV.jpg)
It was the last cartridge in the magazine. Magazines are original CZ. OAL was 1.240" or 31,5mm.
Any ideas what could have caused this problem?
Regards and TIA
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How old is the gun? How old is the mag? There have been some recent threads on this. The oal or amount of bullet shoulder
specifically sticking out of the case tends to be an issue with these style bullets.
Could just simply be a mag spring going weak or just an issue with that particular round of ammo and also if it only happened ONE time you don't have any evidence that there's any issue at hand yet. If it becomes prevalent that's another situation.
If anything I think I'd maybe install some new mag springs and see how the gun performs from there.
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Hi and thank you for your input.
How old is the gun? How old is the mag?
Both Gun and Mags were bought from a collector completely unused. I may have run about 1 to 2 K rounds through this gun.
I did have lots of other feeding issues with the the gun which were systematically eliminated mostly by polishing. But this one is new and unique, als the bullet hit the bottom end of the feeding ramp. When looking into the gun from above one can see that the tip of the top cartridge in the magazine is located approximately 1/4" above the bottom end of the feeding ramp. To hit it the cartridge must make an extreme nosedive when being hit from the back during the feeding cycle.
It seems this will not happen as long as a cartridge sits on top of other cartridges because of the inertia of the other bullets combined with the very low amount of friction between those polished brass surfaces. On the other hand the plastic follower offers more resistance to cartridge forward movement while being very light compared to the lead bullets. A stiffer spring might help pushing up but the follower itself still easily tilts forward quite a lot under pressure. So one might also need mags with more tightly fit followers.
Another Question: How often would you clean the mags inside?
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He asked how old is the gun because there were changes made to the feed ramp depending on year of manufacture.
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The gun is a CZ 97B and is already equipped with the longer feeding ramp.
Meanwhile I found out how to determine the year of manufacture. On my gun the two digit number near the serial# reads "17". So the gun seems to be quite new.
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I wipe mags out after each use just as I clean the gun after each use. If your gun is a 2017 model you should not be experiencing any feed issues. My 97BD has been flawless from day one with over 5 k through it now. If you are using primarily that SWC ammo then yea it's a work in progress to make a bullet designed for revolvers function well in semi autos. I quit wasting time with those years ago as each different .45 I have wanted a different length setting. My cast 225 gr rn's are just as accurate and feed in anything.
At any rate I'd clean everything up real good and see how she behaves. Like I said above until this one failure becomes more than one it's hard to really condemn anything yet.
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I wipe mags out after each use just as I clean the gun after each use.
This is interesting and somewhat in contrast to my experiences and habits with 1911 where I disassemble and clean the gun about every 400-700 rounds (about weekly). But all gliding parts are always kept well lubricated with gun oil that dissolves and neutralizes powder residue. A bore snake ist used immediately after each shooting session.
The all metal 1911 magazines are nickel plated and are wiped occasionally on the outside. Dirt does not seem to stick to the nickel plating. They were never opened or cleaned on the inside for about 10,000 rounds each but still work perfectly.
But I understand that the CZ 97 is a different system and requires different maintenance and cleaning. A learning curve applies. Mags will be cleansed regularly.
If your gun is a 2017 model you should not be experiencing any feed issues. My 97BD has been flawless from day one with over 5 k through it now.
Mine was the opposite with about 10% to 40% of jamming cartridges. I had to polish the feed ramp, the slide area opposite to the extractor and the extractor hook itself. Now that the extractor hooks are polished the former OAL sensitivity seems to be gone. This may be the most important step.
If you are using primarily that SWC ammo then yea it's a work in progress to make a bullet designed for revolvers function well in semi autos. I quit wasting time with those years ago as each different .45 I have wanted a different length setting. My cast 225 gr rn's are just as accurate and feed in anything.
My other gun is a LesBaer 1911 and it will eat almost all kind of ammo without problems. So I aim to develop a perfect cartridge for the CZ97 and hope for the 1911 to eat it too.
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I haven't cleaned the inside of my mags since I've had my 97, probably 700rds. I keep the gun clean, but I'm not obsessive about it. JoeL, a member here shoots his in Bullseye competition and doesn't clean his guns often at all, it's a bit of a running joke for him. FWIW, I load my 200gr coated swc's over Vhit N310 which in my experience leaves the gun relatively clean.
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JoeL, a member here shoots his in Bullseye competition and doesn't clean his guns often at all, it's a bit of a running joke for him.
Well there are so many different opinions about cleaning. For a long time I just did what JoeL still does even including the jokes. Today I prepare for matches by cleaning and slightly oiling the 1911 and shooting one last training session of about 50 - 150 shots before the match. So I know the relatively clean gun is working flawlessly and during the match there is neither excess oil spraying around nor sticky gun grease overly slowing the slide movement. This way the gun is in a repeatable condition with just enough lube and almost no dirt.
Again the CZ 97 is different from a 1911 and may require a somewhat different maintenance routine which I need to develop. I am new to CZ and therefore I am thankful for all your input. Keeping an eye on the inside of the mags seems reasonable. I found some dirt inside and cleaned it out. Lets see...
FWIW, I load my 200gr coated swc's over Vhit N310 which in my experience leaves the gun relatively clean.
I use 4.2gr N310 just like almost everybody around here for all kinds, shapes and makes of 200 gr coated lead bullets. Of course this is not a reloading recipe for you but only an academic remark. This load seems to be THE sweet spot for 45 ACP with clean burning, relatively moderate recoil and even moderate cost due to the tiny amount of powder.
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Looks like the angle on those rounds is "wrong" for feeding out of the magazine up the ramp and into the chamber. If the round isn't "pointed" the at the right angle when the slide contacts it then it probably won't go where it's supposed to go.
A quick/easy check - load the magazine up. Hold it in your hand. Use your thumb to push the rounds out of the magazine one at a time. Look at the angle of each round as it sits at the top of the magazine/feed lips and as you push it out of the magazine. When you get to the last round is the angle different? It shouldn't be different.
Have you had the magazines apart? Sometimes (done it myself) you can get the spring inserted backwards and you get more force on the rear of the follower than on the front. Not good. You want the nose of the bullet forced upwards so the bullet angle is controlled by the magazine feed lips.
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A quick/easy check - load the magazine up. Hold it in your hand. Use your thumb to push the rounds out of the magazine one at a time. Look at the angle of each round as it sits at the top of the magazine/feed lips and as you push it out of the magazine. When you get to the last round is the angle different? It shouldn't be different.
Now comes the crazy unexpected part:
I loaded 10 rounds and removed them one after the other and found that rounds 10 to 7 contacted the round below in the mag only at the base of the case. From round 6 to round 2 they had contact over the whole length. Round 1 was pushed up by the follower just as one would expect. The situation with rounds 10 to 7 remained regardless of shaking the mag violently. So this might be the situation inside the gun when recoil shakes the mag.
But when test shooting yesterday with 10 rounds everything went fine although according to theory rounds 10 to 7 should have caused problems.
10:
(https://i.imgur.com/8bSalsKb.jpg)
9:
(https://i.imgur.com/pvK6XTMb.jpg)
8:
(https://i.imgur.com/Erqha5eb.jpg)
7:
(https://i.imgur.com/r590gn8b.jpg)
6:
(https://i.imgur.com/vsrAPcqb.jpg)
5:
(https://i.imgur.com/ZjD9v5Nb.jpg)
4:
(https://i.imgur.com/c0Iki6Zb.jpg)
3:
(https://i.imgur.com/i7gCUa7b.jpg)
2:
(https://i.imgur.com/2B3kyicb.jpg)
1:
(https://i.imgur.com/wTF1u8pb.jpg)
Have you had the magazines apart? Sometimes (done it myself) you can get the spring inserted backwards and you get more force on the rear of the follower than on the front. Not good. You want the nose of the bullet forced upwards so the bullet angle is controlled by the magazine feed lips.
The mag has been reassembled. The spring was not taken off the follower so the backwards spring problem should not apply.
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I don't have a 97. But on my CZ/Mecgar 9MM magazines the 2nd round contacts the top round - no difference in angles, until I get about half way through the magazine. Then there is small gap for a few rounds (4 or 5) then as I work towards the last round the top and next round make solid contact again.
The last round is solidly against the feed lips and the follower. Tight. If you push on the nose of the bullet down then the follower moves down.
Maybe the 97 magazines are different. It looks like a gap at the front of the round, between the round and the follower (may just be the camera angle or me not understanding what I think I see.) If there is a gap (not good contact with the follower then the nose of the round could be forced downward as the slide moves it out of the magazine towards the feed ramp.
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Maybe the 97 magazines are different. It looks like a gap at the front of the round, between the round and the follower (may just be the camera angle or me not understanding what I think I see.)
The CZ 97 Follower has a ramp and looks like this:
(https://i.imgur.com/4GeUlLMl.jpg)
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And here is the explanation why there has to be the ramp:
(https://i.imgur.com/Xk5n9Kpl.jpg)
The flat area in the bottom right hand corner is where the slide stop is engaged by the follower and pushed upwards. So the ridge coming from the back just has has to end somewhere to get out of the way of the slide stop. And they decided to have the ramp (bright area with the light reflecions) instead of a longer ridge ending in an unstable point. This way the follower can be made of reinforced plastic without breaking but will not support the last cartridge all the way forward. The area where the cartridge sits on the follower is marked by the yellow brass residue on the follower.
With most ammo there will never be a problem. Certainly not with round nose bullets. But with the right SWC bullet set to the appropriate OAL probably fed out of a magazine with a dirty follower producing a lot of friction and if the stars align one can stamp a smiley face onto the bullet.
Ist this a friendly gun or what?
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I've had many 1911's over the years and the one thing they had in common was a desire to have SWC bullets seated at different depths for each one. Same with my 97. That's just the way it is when you're using bullets that were never intended for use in autos.
My 97 will shoot any RN bullet and ANYTHING in the modern hollow point defensive lines so there's just no point in fighting to make the SWC work when there are far better more reliable options.
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I've had many 1911's over the years and the one thing they had in common was a desire to have SWC bullets seated at different depths for each one. Same with my 97. That's just the way it is when you're using bullets that were never intended for use in autos.
I have to admit things can be tricky with SWC. And some bullets will simply not run reliably in a given gun and one has to give up. Sometimes it is the smart thing to do.
But please compare the following two bullets:
(https://i.imgur.com/vnx32yel.jpg)
Both are swaged and copper plated. After plating the right one will be calibrated and the left one plastic coated with transparent material by the manufacturers. I started with the left one and tried every possible length from the shoulder just barely protruding from the case to as long as the cartridge would just fit into my magazines. My 1911 would never reliably feed this bullet. Several years later I bought some packages of the right ones because of bullet shortages. While I mentally prepared for lots of misfeeds to my utter surprise these bullets never jammed on me in the 1911 regardless of OAL. Years ago I used to experiment a lot with OAL and loads to find the perfectly precise cartridge for my gun. I could then do this without even caring for possible jams.
My 97 will shoot any RN bullet and ANYTHING in the modern hollow point defensive lines so there's just no point in fighting to make the SWC work when there are far better more reliable options.
According to your bullet preferences you seem to be reloading for self defense purposes. I do not doubt the reliability of the 97 or any other quality 1911 with those bullet shapes. If these bullets are what you prefer or what fills your needs then there is no reason to mess with the gun or fight non-existing problems.
I shot several packages of Magtech 230gr SWC cartridges through my 97. They ran without any problems while at the same time my handholds would cause huge problems. So why still use 200gr handloads?
Because my hobby is target shooting and therefore I load for maximum precision combined with moderate recoil and nice sharp precise holes as are made by (semi-) wadcutters. Why the latter? If two or more shots hit at the almost same place on the target with round nose bullets it is extremely difficult to judge if two bullets caused that slightly bigger hole or if maybe one or two shots are to be considered missing. With SWC bullets this risk goes away.
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I fully understand the use of the SWC for target work due to the nice holes they punch in paper. I still cast the 358429 Keith style SWC for my revolvers and of course there's never a feeding issue with those. I also have an SWC mold for 9 mm that yields some very reliable bullets but it does seem the .45 can be the problem child with this style bullet.
In retrospect I did have an early Kimber years ago that would feed my cast SWC's at any length and did it very reliably but that was the only one.
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I fully understand the use of the SWC for target work due to the nice holes they punch in paper. I still cast the 358429 Keith style SWC for my revolvers and of course there's never a feeding issue with those. I also have an SWC mold for 9 mm that yields some very reliable bullets but it does seem the .45 can be the problem child with this style bullet.
Bullet casting ist what I am preparing for but did not start yet. Currently the cost for brand factory ammo in 45 ACP starts at about EUR 0,40 each. This ist about US$ 0,46 per cartridge.
I plan to cast for 45ACP only (Lee 6-Cavity Bullet Mold TL452-200-SWC 45 ACP). Maybe there will be another feeding issue surprise awaiting me.
In retrospect I did have an early Kimber years ago that would feed my cast SWC's at any length and did it very reliably but that was the only one.
Initially I expected every pistol to feed every cartridge with 100% reliability all the time. I was so naive. And I was lucky to be offered a 1911 many years ago with all the tweaking and polishing already in place out of the box. And I always shied away from modifying it.
Not long ago I bought "Gunsmithing Pistols & Revolvers"written by Patrick Sweeney.
https://itunes.apple.com/us/book/gunsmithing-pistols-revolvers/id1331847531?mt=11 (https://itunes.apple.com/us/book/gunsmithing-pistols-revolvers/id1331847531?mt=11)
Reading it I found out a whole lot about causes for feeding issues and how to cure them. I warmly recommend this book to every handgun owner. It is definitely worth reading even if one does not plan on becoming a kitchen table gunsmith.
I did not expect having to utilize this newly acquired knowledge with the CZ97 I had bought als "highly tuned and match ready" which it was absolutely not. So I went through all the usual steps of polishing the ramp and so on. At the end it was exactly as Sweeney stated that 80% of all feeding issues can be cured by examining and fitting / polishing the extractor hook. Of course I touched the extractor last and only after trying everything else including varying OAL and using up a lot of ammo just to confirm nothing had changed.
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Hi all,
after a while and trying out recommendations I am just back to report
I wipe mags out after each use just as I clean the gun after each use. If your gun is a 2017 model you should not be experiencing any feed issues.
At any rate I'd clean everything up real good and see how she behaves.
I haven't cleaned the inside of my mags since I've had my 97, probably 700rounds. I keep the gun clean, but I'm not obsessive about it. JoeL, a member here shoots his in Bullseye competition and doesn't clean his guns often at all, it's a bit of a running joke for him. FWIW, I load my 200gr coated swc's over Vhit N310 which in my experience leaves the gun relatively clean.
Thank you all for your hints on cleaning the mag. I disassembled the mag, inspected it and found that there are hard black crusts building up on the follower. These cannot be seen without disassembling the mag as the follower itself is black and not protruding far enough out of the mag. So I removed the crust and still found the follower not to glide as smooth as expected.
To prevent buildup of a new crust I sprayed the plastic follower with silicone oil spray and let it soak in. This also works as a lubricant but in contrast to oil does not attract dust so it can be used in mags. This turned out to work quite well for a while but I wasn't happy with the still higher friction of the follower compared the top notch 1911 mags for the Les Baer.
After thinking about it I disassembled the mags, cleaned them and removed the silicone oil. Then I rubbed the follower with graphite powder and also rubbed some on the inside of the mag housing. This made a big difference in that loading the mag is now so much easier and considerably more fun. When pushing in the first round there is no more friction to overcome only the spring has to be compressed. And the graphite has prevented buildup of a new crust also. It seems that with a clean burning powder (VV N310) a reasonable mag disassembly and cleaning period might be somewhere in between 300 to 1000 rounds.
The graphite thing seems to be the fast and easy way to go. Studying gunsmithing literature (of course after I had found the solution myself the hard way) confirmed the problem with the cartridge diving down and hitting the ramp is attributed solely to too much friction in the magazine.
Regards
Zen
PS. Of course I overreacted a little bit and modified the mags with high- end aftermarket followers. Those I will report on separately.