CZ 452 Disassembly & Trigger Adjustment

[Blindpig]

Just bought a new CZ452 American and have put about 100 rounds through it. So far, I'm very happy. I was looking for a quality bolt-action .22 in a left-hand configuration and it seems to fit the bill.
I'd like to disassemble it and adjust the trigger but I'd like some advice on how to proceed without setting myself up for problems. The manual that comes with the rifle doesn't offer much in the way of detailed explanations.
Anyone out there want to lead me through this?
Thanks a bunch!

[toyfj40]

I'd like to disassemble it and adjust the trigger

are you aware of E.Brooks trigger-kit and his FAQ?
http://www.cz452.com/

[Bullseye]

I haven't worked on one of these but I have shot one. Here's another link to a trigger mod by Fuzzy Limey http://projects.chatrifleclub.org/cz452mods.html

R,
Bullseye

[Blindpig]

I've read Fuzzy Limey's trigger improvments dissertation (wasn't particularly impressed) and looked at Eric Brooks' FAQ's. Neither tells me what I really want to know; how can I find out how much torque to apply to the stock screws when I reassemble the rifle and what "spacer pieces" is Fuzzy talking about? Which way do I want to turn the trigger rod nut to lessen the trigger pull? I'd really like to see some pictures like those that were available when I did the trigger and sear mod on my Ruger Mark II. Anything out there like that?

[toyfj40]

Anything out there like that?

it seems that 1911, ARs, Ruger 10/22 & MKs
get all the user-mods and accessories...
and thus the WebSites/Pages with detailed info...

Since E.Brooks sells the reconditioned Torque-Screwdrivers,
I'd assume he'd know the torques...
or ask him to consider adding it to his FAQ

The RFC/CZ forum is "always busy" and may be a good source.
The CZforum does not appear to be particularly active...
The guys at BR/rimfire occasionally mention CZs.
If you've already seen/tried these then sorry to repeat,
but it's the places I've visited and kept in my CZ-info links...
Good luck. Let us know if you find something else/better.

The CZ-guys on RFC:
http://www.RimFireCentral.com/forums/fo ... y.php?f=18

or http://www.CZforum.com/

or http://www.BenchRest.com/forums/

[Blindpig]

Well, I called CZ-USA and talked to one of their "gunsmiths". He didn't seem like the sharpest knife in the drawer but he did attempt to answer my questions. He says they don't torque the stock screw, just "tighten it down pretty tight". So much for precision. He did ask someone else and relayed to me how to adjust the trigger pull.
I asked him if I would encounter any shims or spacers when I removed the action and he said that some of their models had "things that fall out of the bottom" when the trigger guard is removed, but he didn't "think this was one of them". Glad I'm not sending the rifle in for repairs!
Anyway, thanks for the replies and I'll try to keep you posted on how this turns out.

[Bullseye]

If it's any conslolation, I typically use 22 inch pounds for torquing screws into stocks with glass bedding. That'd be on similar scale of "down pretty tight" but it isn't tight enough to crack the bedding, so it should work for this application. I also put a little anti-tamper strip of nail polish on the head of the screw and the mount, so I can tell if the screw has been removed by the owner. On my own weapons, I use it to tell if any of the mounting screws have backed out from recoil vibration.

R,
Bullseye

[toyfj40]

He didn't seem like the sharpest knife in the drawer

doesn't exactly build confidence, does it...
we can hope that the Sr/Experienced 'Smiths' are doing the work
and making the Jr-smiths answer the phones...

On a lark, I tried a search on: CZ "Trigger Work"
and found this hit on: CoyoteGods.com

Need help with CZ 527 trigger
#81349 - Sun Dec 17 2000 12:05 AM
I just got my 527 in .22 Hornet. It has the set trigger, but I would like to adjust the trigger to make it lighter. Which of the two front screws do I adjust, and which direction to make it a little lighter, and with less slack.
------------------
Re: need help with CZ 527 trigger
#886323 - Sun Dec 17 2000 03:56 PM
There are two adjustment screws on the front of the trigger assembly, and one on the back. The rear adjustment screw is for sear engagement. The upper front screw is pull weight; the lower screw is for over travel.

Turning the upper screw counterclockwise will decrease pull weight.

To adjust over travel, first make sure the rifle is UNLOADED (duh, I know, I know, but it has to be said); now turn the lower front screw clockwise until the sear will not trip (dry fire). Back this screw out until it will, then turn it out an additional 1/4 turn, and lock it down.

The rear screw is for sear engagement, if you do not have much experience with trigger work, I recommend you leave this alone. Improper adjustment WILL lead to accidental Ka-booms. Anytime you adjust anything on a trigger always make sure it is safe. Work the bolt vigorously; rap the butt hard etc., with the safety in both positions. If you don't feel comfortable doing this, a gunsmith wouldn't charge much to do it for you. No shame in that (gunsmiths gotta eat too). I have seen quite a few unsafe triggers in my life.

One caveat, NEVER, EVER, walk around with your "set" trigger activated. These things are VERY sensitive and can go off at a crossword or uncharitable thought. If you set the trigger and don't take the shot, release it by pointing the rifle in a safe direction and pulling the trigger with the safety on.

I hope it is "accurate" and 'helpful'...

[Blindpig]

Bullseye, thanks for the reply on the torque setting. I guess I'm not up on torque wrench applications; enlighten me on that "inch pounds" thing. I thought torque wrench settings were in pounds only???

[Blindpig]

toyfj40, thanks for the reply about the quy with the 22 Hornet. He's got the CZ 527 with the set trigger, similar to the CZ 453. The 452's don't have a set trigger but rather one that is adjustable for weight of pull only.

[Bullseye]

Bullseye, thanks for the reply on the torque setting. I guess I'm not up on torque wrench applications; enlighten me on that "inch pounds" thing. I thought torque wrench settings were in pounds only???

The standard measurement for torque wrenches is typically in seen as foot pounds (ft.lbs). But there is a smaller version torque scale called inch pounds (in.lbs) To convert inch pounds to foot pounds divide the value of inch pounds by 12. Therefore 22 in.lbs is approx. 2 ft.lbs. Inch pound torque wrenchs are typically 1/4" square drive because the torque forces applied are much smaller than the larger torques in ft.lbs. The opposite is true for converting foot pounds to inch pounds multipy by 12. You can buy inch pound torque wrenches at most tool supply stores, even Sears carries them.

Also I found this .pdf manual for CZ 452 rifles maybe it will help you. http://www.czub.cz/navody/cz452_en.pdf
http://www.czub.cz/rezy/CZ_452_2E_ZKM_re.jpg

Hope this helps.

R,
Bullseye

[Blindpig]

Thanks a bunch for that explanation on the torque wrenches. One of the best things about this web site is that your explanations are always clear, concise and on target!
I'd already downloaded and printed that pdf file for the manual. It's the same one that comes with the rifle but much easier to read because of the size and the fact that you don't have to wade through the other languages to get to the English.

[Blindpig]

Well, I took the 452 apart over the weekend, adjusted the trigger and put it back together. Came apart smoothly and went back together the same way (no left-over parts)! Guess I'll order one of Eric Brooks' kits.
Bullseye, I thought about buying a torque limiting screwdriver so I went to my Brownell's catalogue. Big surprise!! Those little puppies are nearly 220 bucks! My wife gets a little steamed over the amount I pay for my guns; I can about imagine what she'd say about a $220 screwdriver!

[Bullseye]

$220 for a screwdriver is a bargain by government standards. Remember the $600 toilet seat? Seriously, I know that isn't in the normal household budget but there's some other reasonable beam type torque wrenches that work just fine for what you're planing on doing with firearms. There's even some good click type wrenches available that aren't very expensive; you don't have to use a torque limiting screwdriver. Torque is torque! It doesn't matter what you use to set it, just set it to the right value.

R,
Bullseye

[Blindpig]

Bullseye, thanks for the reply. I'll start looking in the tool stores here in Tulsa and see if I can find a torque wrench that's a little more affordable.
I noticed on Eric Brooks' web site that he has reconditioned torque limiting screwdrivers available for about $70. I've never ordered anything from him but I was thinking about getting one of his spring kits for my 452. Is he reliable, do you think?
By the way, are you saying the toilet seats in your house cost less than $600?