Rimfire Central Firearm Forum banner
1 - 20 of 22 Posts

·
Registered
Joined
·
1,135 Posts
Discussion Starter · #1 ·
Several people have ask for pics of the trigger shims I described in the topic "CZ American Trigger Work Problem" on this forum. I just took these a little while ago with the trusty Nikon.

The first shows one of the shims under placed between the receiver and the part of the trigger that holds the staked pin. Remember that theres another shim just like this one on the other side (2nd picture).

Warning I should have mentioned in the other post: Anyone that doesnt know EXACTLY what they are doing should not mess with a CZ trigger, or any trigger on any gun, for that matter. If you get the brass shim too thick, the gun might go off when the bolt is closed, or when the gun is jarred. I recommend putting a little sticky stuff on the shims so theyll hold in place for testing, and test the engagement with the rifle unloaded. Do this by slamming the bolt closed several times and/or firmly bumping the butt on a pad on the ground. If the firing pin falls, then make the shims thinner. ALWAYS err on the side of safety. Dont try and remove the last tiny bit of creep. Use some type of glue that you can easily get out if you need to modify shim thickness later (I used JB Kwik).



 

·
Registered
Joined
·
1,410 Posts
I wasnt sure where you meant the shims were supposed to go but the pictures cleared it all up. Thats so simple. I originally had the aluminum tape wrap creep fix, then I went to a brass ball point pen refill tube over the forward pin, with a ball point pen trigger spring, and although the trigger pull was 8 ounces, there was sill alot of creep, so yesterday I removed it and used a 5/32 inch copper tubing over the forward crosspin. Now there is negligible creep and still the 8 ounce trigger pull.  Im real good at reinserting the detent ball. ;D
 

·
Registered
Joined
·
1,793 Posts
When I put the brass tube over the front pin I did not have to take out the sear and thus did not have to crawl around looking for the detent ball.  I just used a punch to knock out the two trigger pins.  Is there some reason to remove the sear?

I measured the pull without any spring and it came in around 8 ounces.  I would guess that the light spring contributes next to nothing to the pull.  However it also means that you cannot go lower than 8 ounces without reducing friction in the trigger/sear area.

I used a spring out of the local hardware store - almost the same size as the original but much lighter.  Im at about 1 lb right now but need to increase it to 2 lbs for Hunter Silhouette.  I have some other springs on order that should be here soon - that should give me a wide range of pull adjustment.

What creative solutions have been used to reduce overtravel?
 

·
Registered
Joined
·
217 Posts
I just finished doing my trigger following the tip from Forester on my Special. I used a pop can for shims. I folded the strip twice, making it four strips thick. It would fire if I put the safety on then took it off, so I pounded the shims down a little with a hammer. I havent been able to make it fire no matter what I do now: slamming the bolt, pounding the butt on the floor, taking the safety on and off, and pulling the trigger with the safety on. It wont fire when I take the safety off either. So now the trigger has no creep, and feels lighter. I dont have a trigger scale, but I imagine its somewhere around two pounds or maybe a little more.
The trigger is good for being at the range, but Ill probably change it to only one or two thickness shim for hunting. Great tip Forester!

peashooter
 

·
Registered
Joined
·
1,410 Posts
To adjust overtravel, the trigger spring rod needs to be lengthened so that it touches the bottom of the bolt sooner and shortens overall trigger pull. I have heard of the rod being made longer by peening it to stretch it or by adding JB Weld to the end. This info was from Nick in Bangkok. Concerning the detent ball, I could not get the trigger front crosspin out while installed on the rifle. Not being as mechanically adept as yourself in the ways of gunsmithing, I needed to disassemble the sear and trigger to remove the crosspin.  
 

·
Registered
Joined
·
1,135 Posts
Discussion Starter · #7 ·
Brookie, over-travel is pretty easy to fix, but theres really only one way to do it.  If you stop the trigger with any method other than contact with the top of the sear, the you wont be able to get the bolt out of the rifle.  Making the spring rod longer doesnt really stop the trigger, it just puts a catch in its movement.  There are a couple of suggestions for building up the top of the sear at the following web site:

http://www.geocities.com/fuzzylimey/cz452mods.html

This is not too easy a fix.  Youve got to deal with drifting out pins and that nasty ball bearing.  But it works really well.
 

·
Registered
Joined
·
4 Posts
Forester, thanks for the pics. I have the American also and will be attempting a bit of tweaking.
The pics look really quite good for close ups. Mind telling us what kind of Nikon youve got?  I am assuming its a digital cam, but mabye not? Also, whats that one set you back?
 

·
Registered
Joined
·
4 Posts
Thanks Forester. Update on the trigger job. I got the #C-582 spring at the local Ace store as well as the C-580. The 582 was too light for my liking (even after doubling the springs together) I dont know what the pull was, it was very nice but if my kids wound up using the gun it may be a prob. The 580 was of course too small in dia. and would have never worked even if I would have gotten it over the rod.
Rather than use the foil wrap method on the front pin of the trigger trunnion I removed the pin and sleeved it with a pice of brass tubing that the pin just slipped through. It is .125 o.d. I thought this might be too thick as per instructions on "trigger Mods" so I cut off three inches of the tubing, ran a rod through it for support and "poor mans lathed it on the drill press with a file and wet/dry until it was a fairly uniform .120. Then cut off a piece that would fit. Origional pin dia. on my trigger trunnion was .098. I think I could have just used the tubing  as is, but I didnt want to unstake the pin and remove it more than I had to.
As for the sear/trigger, mine was atrocious. I have a dental lab and just smoothing them up was easy and made a big difference.
Back to the spring: I got a couple of other springs that looked heavy enough (.028) but couldnt get them to my liking (still too light) so I ended up putting the origional back in. I was expecting that old bad trigger, but with the other improvements It feels pretty good. Mabye still somewhat heavy, but very little creep and  a great improvement. Im not going to worry about overtravel right now, mabye never, unless my tastes become more refined.
Hope this long ramble may help someone. This site has helped me. Thanks.

P.S.: I forgot to mention that when removing the pin in the trigger trunnion (the one were told not to remove) I made a piece of metal that just slipped inbetween the two sides as I was afraid that if I hammered too hard in attempting to get the pin out I could possibly break the trigger trunnion as it looked cast. Mabye not But I didnt want to have to find another one.  HTH. The cool smily face is supposed to be an eight.
 

·
Registered
Joined
·
1,793 Posts
Mr_Browning - You had some interesting innovations in your approach to the sleeves - you got me thinking.

I am selling a parts kit with a set of 4 springs and 2 different sleeves.  I had special ordered a variety of springs, but most came in sets of 12 so there were a lot left over.  I was mainly looking for a spring suitable for the minimum Hunter Silhouette pull weight of 2lbs.

The springs provide a range of pull weights on my gun:

Description      Min Pull      Max Pull
No spring             0.50      0.50
Extra Light           0.75      1.00
Light                    1.00      1.25
Medium                1.50      1.75
HS Spring             2.00      2.50 (HS = hunter silhouette)
Factory Spring      3.00      3.75

(The "No spring" and "factory spring" are for reference.  If your "No spring" figure is lower due to polished surfaces, etc, then the other pull weights are likely to be lower also.)  They are all similar in size to the factory spring and drop in without binding.

There are also 2 brass sleeves cut to size (to replace the aluminium tape) of 0.014 and 0.018 thickness.  The thickness of the sleeve is more important than the OD.  They both eliminate a bit of the creep without going too far.  They are roughly 5/32 OD.

The kit sells for $9 including shipping.  E-mail me if you are interested.
 

·
Registered
Joined
·
4 Posts
Thanks Brookie. I am going to try out what Ive got (not today, dang it) and see how it goes. I must have spent ten bucks in gas going all over town looking for tha right spring. A kit is a great idea.
Im new to this trigger mod stuff, so Im sure I dont have what I could have as far as the trigger goes, but it took alot for me to fool with it at all. Oh my! Fooling with the trigger! :eek:
 

·
Registered
Joined
·
1,135 Posts
Discussion Starter · #14 ·
Glue 'em in with your favorite brand of epoxy. I used JB Kwik. Make sure they are not too thin (still creepy) or too thick (unsafe) before you glue them in. Good luck.
 

·
Registered
Joined
·
76 Posts
This is too easy!

Last week, after ordering Brookie's trigger spring kit, I went to Ace and got the light spring and installed it in 10-20 mins. The trigger was very light (OK for bench but not for hunting), but it still had noticeable creep. Tonight I cut some brass shims from an old .303 British shell casing (0.015" thick), cleaned them up a bit and JB Kwik'd 'em on. This after a dry fitting, of course. It works great and is soooo easy! No creep and a light trigger (est. 1 lb.) in 30 mins. or so. I love simple mechanical devices like this. These triggers are very easy to perfect if you are mechanically inclined at all. Brookie's kit will still be useful as it gives me a selection of trigger pull weights for different applications.

Thank you CZ. :t
 

·
Registered
Joined
·
1,213 Posts
Trigger overtravel...

Forester : the peening/lengthening of the trigger spring guide rod to reduce overtravel had been done here for more than 20 years. The rod stops on the bottom surface of the bolt. When one opens and pulls back the bolt as one would do to take it out, the front portion of the bolt, with the bottom milled off, will allow the trigger to be pulled further back, releasing the bolt.

Personnally, I don't like peening the piece. Brookie's sleeve is the most elegant solution. Your shimming the easiest and most efficient.

For sleeving with Brookie's tube, punching that front trigger pin out while it's on the gun is easier and safer than doing it outside. The receiver prevent the two ears collapsing.

For guns made until early '70, there is no hassle of the sear ball. It was a plunger then. This make removing/replacing the sear much easier. To avoid punching out the staked pin, keepin the gun in original condition, we used tape on those old guns.
 

·
Registered
Joined
·
1,633 Posts
Trigger shims/Brookies kit

Save yourself a lot of time & frustration not to mention wasting gasoline. Order Brookie's spring kit. I had mine in three days of ordering & had it installed in less than 15 minutes.
This kit gave better results on my 452 American than the Spec Tech match trigger I intalled on my Ruger 77/22 vbz.
The Spec Tech is a good unit,however the cost is approx. $100.00.
Brookie's kit costs $9.00. Who said there are no bargains in this life?
Keep up the good work Brookie.
Rod.
 

·
Registered
Joined
·
1,135 Posts
Discussion Starter · #18 ·
Nick, I would call it "Brookies" spring kit, but I figure it's your "sleeve method." You've been doing it long before most of us ever heard of CZ. I agree the sleeve method is the most elegant solution to this problem. But I'm a lazy type, and I hate driving out more pins than is absolulely necessary. Good luck to you and thanks for all the good posts.
 

·
Registered
Joined
·
1,213 Posts
Speaking of lazy, I'd say... Me Too. That's why the tape stuck with no further improvement - while several people had demonstrated that it's possible.

Brookie is spoiling us. He should be credited for doing all the hard work. He did the testing for spring and tube thickness, get the proper parts together and ship them directly to our doors. All I did was noticing where the pin rest and stop. It's Brookie's sleeve that's included in his spring kit. And his method keeps the ball in it's place too. ;)
 

·
Registered
Joined
·
414 Posts
Hey guys...

On the creep part of it. I just bought my CZ American in .17 HMR, and I adjusted the nut all the way down. I had NO creep at all, just a very clean break. Before firing the gun, I cleaned the barrel and action completely, including the trigger assembly and the bolt, which I took apart. I reassembled the whole gun after a very light oiling. After oiling, I had about 1/8" of creep that was not at all present before. I removed the barreled action from the stock and wiped off all excess oil from the trigger assembly, and all excess oil from the bolt housing that could flow into the top of the trigger. Once again, the creep is nonexistant. What would cause this?
 
1 - 20 of 22 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top