Need recoil spring help!

[Old Coastie]

I need to replace the recoil spring in my .40 cal. CZ100. I was at the range yesterday doing a little practicing. During the session I switched from 165 to 180 gr. The 180's were Winchester white box. While retrieving the empties I noticed that I am getting primer wiping with every case, but only with the 180's.

Does CZ or Wolf make a heavier recoil spring? I don't even know what the factory spring is. All I know is that it is blue and not strong enough. The empties are being thrown a good 15 feet. Way too far I think.

Please help. If I can solve this problem and one other I believe I will have the perfect self defense pistol, bar none.

Thanks in advance.

Mike

[dleong]

Mike,

You are not the only one to notice that the 40S&W CZ 100 is rather undersprung. I currently shoot fairly mild handloads (155 gr. Rainier TMJ over 6.2 gr. of Universal Clays at an OAL of 1.130") through my CZ 100, and the frame battering on recoil is quite disconcerting.

A couple of months ago, I telephoned Wolff Springs and inquired about the availability of aftermarket recoil springs for the 40S&W CZ 100. No dice. However, the lady with whom I spoke said she would pass the request on to their technical department. If enough CZ 100 owners call them about this issue, they might add it to their product line. Realistically, though, I doubt the current market for CZ 100 pistols is large enough for this to happen. I do not know if heavier recoil springs for the CZ 100 are available directly from CZ-USA.

It is entirely possible that a recoil spring intended for another pistol might work in the CZ 100. I used a micrometer to measure the various dimensions of the factory recoil spring in my 40S&W CZ 100. Here are the measurements:

Outer diameter:      0.413"
Inner diameter:      0.250"
Coil wire width:     0.078"
Coil wire thickness: 0.026"
Loops in spring:     30
Approximate length:  5" (after set)

Perhaps Wolff might have a spring with these dimensions intended for another pistol; I have not called them yet to inquire.

DL

[kahrpacker]

Check the information on Wolff site:

gunsprings.com

Bren

[Old Coastie]

Bren,

I give up. What am I supposed to see at the Wolf site? I found no mention at all of the CZ100. Others have called them and been told that they make no springs for the CZ100.

Did I miss somthing?

Mike

[lee n field]

The first (and so far only) box I've shot through mine was the same Winchester 180 grain ammo.  Cheapest thing Walmart had.  I checked the brass I scavanged.  Every primer was that way.  Scary.  So, I won't be getting that again.

Re the spring -- my brass was landing about 7 or 8 feet behind me and pretty close together, which is tolerable by me.

[Old Coastie]

Well, I talked to Mike at CZ-USA today. I told him about the primer wiping with Winchester 180 gr. FMJ. He told me that it is not a problem. Apparently CZ-USA is OK with the barrel beginning to unlock from the slide before the firing pin is retracted fully. I guess I'm supposed to continue firing it until some day when the spring weakens a little more the darn thing blows up in my face. NO THANKS!

Has anyone out there found a source of higher power replacement recoil springs for the .40 cal. CZ100?

Help!

Just want to add that in fifty plus years, I don't think I have ever talked to a more condescending person than Mike @ CZ-USA.

Mike in Cincinnati

[ndeeya]

i'm new to handguns,

could u explain what exactly the problem is?

there is primer on the casings?  what does that tell u about the barrel, slide and spring, and ammo?

also the distance the casings are being thrown... is farther away worse that closer?

thanks, maybe i can avert a kB with my gun if i understand it better.

-andy

[Walt-Sherrill]

Quote:Well, I talked to Mike at CZ-USA today. I told him about the primer wiping with Winchester 180 gr. FMJ. He told me that it is not a problem. Apparently CZ-USA is OK with the barrel beginning to unlock from the slide before the firing pin is retracted fully. I guess I'm supposed to continue firing it until some day when the spring weakens a little more the darn thing blows up in my face. NO THANKS!

I'm not sure I understand your point.

If the round has already fired -- the recoil cycle has begun with the casing still in the chamber, held there by the casing being expanded against the chamber walls by gas pressure -- how is the gun going to blow up in your face?  The primary explosion has already taken place, sending the bullet down the barrel.

Once the bullet is fired and the recoil cycle has begun, it seems to me that there's nothing that CAN blowup in your face until the next round is chambered.  If the firing pin is still extended at that point, then something other than the RECOIL SPRING is the problem.  

(Perhaps I misunderstand your point, or the workings of the recoil cycle...)

Maybe a stronger firing pin spring -- like the Wolff spring they send with every recoil spring -- is what is needed?

[Old Coastie]

Walt,

Normally the barrel is locked to the slide until the bullet has left the barell. What happens if the recoil spring is underpowered, however. When the pistol is fired the slide will recoil at higher speed and will begin to unlock from the barrel sooner (in absolute time ). The time the bullet is in the barrel is fixed. Therefore, the weaker the recoil spring, the sooner the barrel will begin to unlock from the slide, with respect to bullet travel/pressure in the barrel. Will it blow up in my face? I doubt it. What are the odds that anything serious will happen? Somewhere between slim and none? Do I want to test this? Not me! I tend to be somewhat on the unlucky side in these matters.

From a practical standpoint, if your recovered brass exhibits oblong primer indentations, I was taught to do one of two things. Reduce my powder charge ( not possible with factory ammunition ) or use a higher power recoil spring with an increased weight firing pin spring.

I would love to do the latter. That is why I began this post. Who makes recoil and firing pin springs for the CZ100? Any suggestions?

Mike in Cincinnati

[Walt-Sherrill]

Since you've got a fully supported chamber, the chances of a kaboom seem pretty slim.  I

 understand your discomfort, but also think CZ wouldn't be too cavalier about the problem if they felt there was any real personal danger (or, more important, corporate liability) involved.  

Seems like the problem you mention would be present anytime you have an undersprung gun, and that isn't isn't usually the case.  In those cases, the slide just sling the brass farther, and batters the slide stop more noticeably.

I wonder if your FP spring is giving up the ghost?  

I would think, too, that if the barrel was unlocking BEFORE the bullet has left the barrel, the point of impact would be changing -- it would almost have to be higher than expected, wouldn't it?  (Since the barrel was already rocking back...)  Have you noticed that, as well?

We've already found, in other message chains, that CZ-75B springs can be adapated to CZ-40Bs, if a couple of coils are cut from the spring.  (3-4?).   I wonder if the same process will work with the CZ-100?  I also wonder if the firing pin spring will work in the CZ-100, too?   (Or maybe you can just order a new one from CZ.)    Might be worth ordering an extra-strength CZ-75B spring to find out.

[Old Coastie]

Walt,

You make some interesting points.

I never really thought that the barrel was unlocking from the slide with the bullet still in the barrel. Only speculating that it could happen with a seriously weak recoil spring. Mine shouldn't be anywhere near that yet, as the pistol only has about 60 rounds through it.

I am also not ready yet to begin changing out springs with other springs not made for the CZ100.

My plan is as follows:

Buy and test a different brand of 180 gr. ammunition.

When the 9 mm CZ100 I ordered comes in ( am I bad or what ) I will compare the recoil springs from both pistols. It seems to me that the .40 S&W should be heavier than the 9 mm version.

If they appear the same, I will order a recoil and firing pin spring from CZ-USA and send them off to Wolf to see if they have anything in stock that is similiar but higher poundage.

Only then will I consider attempting to use a CZ75 spring set.

If all above fails, I guess I just won't use 180 grain bullets.

Thanks for challenging me. I fires up some extra brain cells which sit dormant too much.

Mike in Cincinnati

[Walt-Sherrill]

I don't think you'll find the spring in a .40 different from that found in the 9mm version.  

As best I can tell, they use the same spring for guns with the same frame size, regardless of caliber.  

(Wolff certainly doesn't give you a choice of "caliber" when ordering the after-market springs.  I'm too lazy to look it up, but I think they use the same springs in the big-framed .45 Witnesses, too.)

Frame size, more than caliber, dictates the use of a different spring.  

When you do send them off to Wolff, please let us know what they recommend for you.