Inexpensive CZ 457 Light Trigger Spring Option

[BC-2]

I recently picked up a new CZ 457 and like many, found the trigger to be a bit heavy. I was looking at the various trigger spring options such as the YoDave spring and others on eBay. I was about to order one on eBay, when I decided to take the stock trigger spring out and see if I had anything that might fit but with a lower rate. To my surprise, a spare safety plunger spring I have for my Glock Gen 5 was the same length, just a tad smaller in diameter but much lighter in rate.

I installed it and I can easily get under 1lb pull and functions perfectly. I didn't want it this light so I adjusted a little heavier to 1lb 4oz and is well in the range of adjustment. I have no idea what the spring rate is on the safety plunger spring but it works great. Just a heads up!

 

[AirGunShawn]

Try McMaster Carr...
9657K611..... for a .014" spring
9657K612..... for a .018" spring. This was the size that I got from YoDave 2 years ago.

#49 is backwards..... turning the screw inwards reduces sear engagement.
I suggest that you turn the screw in until the FP drops on a snap cap and then back out about one quarter turn as a starting point.

When you drive the trigger pin out you will notice what a PITA it is. I HIGHLY recommend that you sand down one end of the trigger pin
with some 220 wet / dry. It will only take a few seconds. As soon as the trigger blade slides over the pin it is complete.

Shawn

 

[Booner1334]

This is a very timely post for me. Thank you both for posting this.

 

[sarpaul]

I'm using a spring from a clicking pen.
Same outside diameter, and the price was right...

 

[BC-2]

Try McMaster Carr...
9657K611..... for a .014" spring
9657K612..... for a .018" spring. This was the size that I got from YoDave 2 years ago.

#49 is backwards..... turning the screw inwards reduces sear engagement.
I suggest that you turn the screw in until the FP drops on a snap cap and then back out about one quarter turn as a starting point.

When you drive the trigger pin out you will notice what a PITA it is. I HIGHLY recommend that you sand down one end of the trigger pin
with some 220 wet / dry. It will only take a few seconds. As soon as the trigger blade slides over the pin it is complete.

Shawn

Thanks for the tips!

 

[bunny too]

The #144 spring from Ace hardware works very well for $0.49. You can also get a Fastenal 159A, 160A, 161A or a 162A and replace the factory spring in you want something in the 8 oz to 1.5 pound range.

 

[AirGunShawn]

If you would like to lap your trigger sear while you have the trigger out, I have used some 9 and then 3 micron aluminum oxide
PSA backed lapping film. Any hard flat surface works fine. Granite counter top, back of kitchen plate or you can even buy a piece of floor tile from
Lowes or Home depot. Meaning that you don't need to use a surface plate like I happen to have. To retain your trigger pin you can use fingernail polish or you can use a prick punch to Stake it in place. I used to sell kits to do this for those who wanted to take the turn key approach.
I used to send out four springs, lapping film, moly grease, and silicon grease as an assembly aid with instructions of what to do and why..... Six oz. is about as lite as you can expect a 457 trigger to get and I use all of my guns as bench guns meaning that they don't get bumped around much.
If you lap the trigger, do so at 90 degrees to it's pivot pin. Don't round over any edges.... keep them sharp and crisp.
One more thing I would like to mention is that the trigger sear is huge and virtually self leveling and easy to do. If you try the upper Trigger Bar sear
you will likely alter it's profile and wish you had never touched it.

My favorite arrangement for my MTR is a Vudoo bolt knob an Anarchy outdoors extended magazine release and a ACE trigger shoe.

I just measured a ball point pen spring and it has an OD. of .220 and just cant fit in the housing. Good luck if you choose that approach.

 

[BC-2]

If you would like to lap your trigger sear while you have the trigger out, I have used some 9 and then 3 micron aluminum oxide
PSA backed lapping film. Any hard flat surface works fine. Granite counter top, back of kitchen plate or you can even buy a piece of floor tile from
Lowes or Home depot. Meaning that you don't need to use a surface plate like I happen to have. To retain your trigger pin you can use fingernail polish or you can use a prick punch to Stake it in place. I used to sell kits to do this for those who wanted to take the turn key approach.
I used to send out four springs, lapping film, moly grease, and silicon grease as an assembly aid with instructions of what to do and why..... Six oz. is about as lite as you can expect a 457 trigger to get and I use all of my guns as bench guns meaning that they don't get bumped around much.
If you lap the trigger, do so at 90 degrees to it's pivot pin. Don't round over any edges.... keep them sharp and crisp.
One more thing I would like to mention is that the trigger sear is huge and virtually self leveling and easy to do. If you try the upper Trigger Bar sear
you will likely alter it's profile and wish you had never touched it.

My favorite arrangement for my MTR is a Vudoo bolt knob an Anarchy outdoors extended magazine release and a ACE trigger shoe.

I just measured a ball point pen spring and it has an OD. of .220 and just cant fit in the housing. Good luck if you choose that approach.

I may try your tip on polishing the sear. It's not bad stock but it could be more crisp. I plan to shoot rimfire silhouette and maybe some NRL22 type matches so I didn't want to set my trigger too light. Thanks again!

 

[gkgeiger]

I’m using the eBay spring and a Scar pivot pin in both of my CZ’s. I’m happy with the way it works.

 

[JKW70]

I bought both of the McMaster Carr springs. I’m running the smaller one in both of my 457’s. One pulls 7oz the other pulls 8. I also have the Scars pivot pins in both and highly recommend them.

 

[MarshallDodge]

I'm using a spring from a clicking pen.
Same outside diameter, and the price was right...

I learned this trick from a friend, who would do this with the H&R handi rifles, and tried it on my 455. Works like a champ.

 

[Dio]

I have a 10oz trigger after installing this one in my 457.

CZ 457 Series Rifles, ALL Calibers, COMPETITION Trigger Pull Reducer Spring 8oz | eBay

• Will ONLY work on CZ 457 series rifles. ALL CALIBERS. CZ 457 Series Rifles Trigger Reducing Spring down to 8 oz +. Condition is "New". • Reduce your trigger pull down to 8oz. Your results may vary.

www.ebay.com

 

[AirGunShawn]

I am in no way condemning any approach someone else takes to solve a problem. I do however think it's ridiculous to
suggest a ball point spring pen or a spring from the hardware store or any other approach that lacks the information that will
make it possible for the other SH members to be successful at changing the spring in the 457 unit.
Hell... I'm not above using a pen spring as a preliminary test but I would never leave it in one of my guns that will eventually be
sold to someone else.
The spring has to go in between the walls of the housing unit and the trigger has a spring pocket that it must fit into. See photo #1

If a person wanted to they could use McMaster Carr #9657K601, 602 or 603 as a replacement as well. They are .25" long with a .148" OD and have wire diameter of: .021", .018" and .014". I took the time, spent the money and decided it would be unsafe for virtually everybody on SH.

If you do lap your trigger sear with the 9 and then 3 micron PSA backed film, you will find that it will take about 35 minutes to get a near mirror polish on the chrome plated trigger and under ten minutes for the black trigger.

The opaque silicon grease shown in the photo is not used as a lubricant but as an assembly aid. It is very helpful to pack the trigger spring pocket full of grease to hold the tiny spring while you try and line the spring up with the set screw #53 centerline. If you remove screw # 53 completely you can insert a toothpick or some other small guide to help align the spring. If it is not done properly you wont know it until you have reassembled it and found the spring pre-load to be to high. BTW.... The centerline of screw #53 is also the centerline of the spring.
The guy that did the sketch failed to show it or clearly note it.

All that being said.... the lap and spring replace is one of the simplest and straight forward triggers that I have ever seen but a little
guidance, support and clarification to questions can go a long way to those who didn't spend thirty years in mechanical design.

If you have any questions I'm happy to help.... even if you just need to borrow some confidents.

Shawn
I can also be reached on my email on the glider photo. ks_carroll
It's much faster than my SH connection.

 

[AirGunShawn]

When I bought my MTR I hated the small round ball they had for a bolt knob and the stupid short magazine release. So I bought a AREA 419 knob and it looked funky but it felt and worked great. After I bought my Vudoo, I realized that their knob was the perfect balance of size, weight and texture.... at least for my taste. So I bought a Lumley thread insert and now have a Vudoo knob on all three of my 457s. I have also replaced all of the magazine releases with Anarchy Outdoors Ext Mag release. I had DIP release's but they are only 2mm ( .080" ) longer than the standard
CZ release so I' was still having to dig for them. The trigger shoe is an ACE #24 and can be found on GB or eBay.

 

[BC-2]

I am in no way condemning any approach someone else takes to solve a problem. I do however think it's ridiculous to
suggest a ball point spring pen or a spring from the hardware store or any other approach that lacks the information that will
make it possible for the other SH members to be successful at changing the spring in the 457 unit.
Hell... I'm not above using a pen spring as a preliminary test but I would never leave it in one of my guns that will eventually be
sold to someone else.

I would personally never use a pen spring or something completely random as these components are generally not made from quality materials but if others want to, that's certainly their choice. I was a bit apprehensive about even making my original post because the Glock Safety Plunger spring is slightly smaller in OD than the original CZ 457 spring. However, it is the same length and while I don't know the spring rate, it produces the exact range of trigger pull weight I want. Most importantly, I feel it is safe to use as it is presumably high quality spring steel, made for a high volume of cycles in a firearm (Glock 19). It can also be purchased for about $3. For this reason, I ultimately decided to share my findings by making this thread.

BTW Shawn, I followed your earlier tip on sear engagement and it helped significantly. My trigger breaks with no creep and is very crisp. I honestly don't feel I need to do anything else! Once the sear engagement was adjusted, I did notice my pull weight went from 1lb 4oz prior to the adjustment, to 14oz after. This was without touching the trigger spring preload (tension) adjustment. While this is a bit lighter than I would have originally wanted, It's really nice so I think I'll try it out like this as I can easily stiffen in up later should I feel it's too light. I know people set theirs much lighter so I think it will be okay.

 

[AirGunShawn]

BC..... When I bought my first kit from Y-D, I thought that $20.00 was absurd for one spring and a block of white poly.
I spoke with him and he told me that he had the springs custom made and I thought something like you lying POS.

I spent 30 years in design and we only go custom when we have to. I checked MC and found them within ten minutes so
I decided to put together a kit with four springs, lapping film, grease and instructions. I put together a package to promote
success for the average guy with little skills and the absolute minimum in tools. I lapped one trigger on my laptop to demonstarte that it could be done almost anywhere. I suggested that you could adhere the lapping film to a kitchen plate. You don't need a granite surface plate, micrometers or dial calipers. When you sand one end of the trigger pin down with some 220 wet / dry the best tool to measure it with is the trigger blade itself. The factory put those dimples into the pin to retain it. They are called STAKES. The pin has an hour glass shape to it. The ends are about .003" larger than the middle is.
The prick punch in the last photo is a stake to hold the pin in. Personally I use finger nail polish. I only offered the stake as an option for those who felt uncomfortable with FP. I DONT use Loc-tite on triggers nor does Anschutz, it can wick into the joints.

In this case, spring rate and pre-load are a waste of time for the end user. I had to know it to calculate springs used in my designs
when they were on paper. They give you the rate at MC but it is really meaningless for anyone who is simply replacing the trigger spring.
People don't know what the factory rate was so they simply use the next smaller wire dia. They don't know if the factory spring is Music Wire or stainless steel. From memory, a spring made from SS has a rate that is 13% less than one made from MW. ( high carbon ) that is the same physical size.
Spring life cycle is based on a couple simple things, so even a ball point pen spring will last forever. The speed, heat and total deflection are all near zero so it's a mute point.

Hope this has been helpful to at least one person...

Shawn

I prefer 6 / 8 oz triggers on my 457s.

 

[rookie7]

Thanks to all for this thread!

 

[MarshallDodge]

I am in no way condemning any approach someone else takes to solve a problem. I do however think it's ridiculous to
suggest a ball point spring pen or a spring from the hardware store or any other approach that lacks the information that will
make it possible for the other SH members to be successful at changing the spring in the 457 unit.
Hell... I'm not above using a pen spring as a preliminary test but I would never leave it in one of my guns that will eventually be
sold to someone else.

......

Fair enough but we are discussing making modifications to a trigger by a couple of kitchen table gunsmiths. In my case, the pen spring worked perfectly and has for a half dozen bricks of 22LR.

Is modifying any trigger outside of how it came from the factory safe?

To suggest that you are above all this is a bit pretentious considering the advice that you are offering is to the same audience.

Triggers are never to be trusted under any circumstance, and to suggest that yours are safer than another is pretty ridiculous

 

[AirGunShawn]

No need to take it personal. I really don't care if everybody used ball point pen springs. I wouldn't because I know better.

Having 3K in ammo down the barrel doesn't ensure that the gun is safe. The company that I worked for, the largest automotive tool supplier in North America, designed, built and sold Ford Motor company 6 lifters to raise 8000 pound tools and they worked fine for a couple months until one of them broke and dropped one of those tools.

After doing one calculation on the idler shaft It was clear that our company blew the shaft. The allowable deflection over four feet should have been .040" It's actual deflection was .125" In the calculation I dismissed the two 3/4" keyways and the Von Mises stress concentration that would have been created by the sharp corners while machining the keyways. Meaning they blew it even worse.....

The trigger was designed and built to company standards. That meant a designer modeled it up on the computer, proto-typed it and then it was tested. After passing certain criteria it was deemed as safe enough for it's intended use by that particular company or standards that that company must adhere to by some governing board.

If I had doubts about my ability to make safe judgements about my own guns I would not alter them. My alterations are always made in such a way that I can put them back to factory specs. I also would not rock climb, scuba dive, hang-glide or have gotten my LSA rating for airplanes.

If it sound like I think my judgement is superior to most other people when it comes to mechanical crap.... I do.
My title at work was design / check the top of the food chain. I am the guy that keeps stuff from crashing down on you.

Ultimately all I really was doing was offering an alternative to the ball point pen spring. And I don't recall suggesting that mine could somehow be safer due to a different spring. That would be ridiculous. It's a spring......

On a side note... every time I see someone talk about springs and their rate I cant help but feel they are being a little pretentious but I just chuckle to myself.

Shawn
Comau LLC

Fair enough but we are discussing making modifications to a trigger by a couple of kitchen table gunsmiths. In my case, the pen spring worked perfectly and has for a half dozen bricks of 22LR.

Is modifying any trigger outside of how it came from the factory safe?

To suggest that you are above all this is a bit pretentious considering the advice that you are offering is to the same audience.

Triggers are never to be trusted under any circumstance, and to suggest that yours are safer than another is pretty ridiculous