Trigger spring replacement

[EddieE]

For those that haven't done it yet...what are you waiting for? It is super easy once you watch one of the many videos out there.

I used this spring and made a huge difference in the weight. I don't have a scale to check the weight, but it is significant. AND it passes the bump/drop test. The only issue I have is that it is not stocked at my local store. And it cost me a total of about $15 for two.

https://www.fastenal.com/products/details/0166659?term=162-A

Next modification is the pillar posts and glass bedding the stock. I will see a gunsmith for this. I feel like I will forget to wax some part of the action and it will stick to the stock

I have a really good smith about 40 minutes from me who will probably let me hang around while he is doing it for me and I can watch. The guy is close to 80, looks like he is 60 and sharp as a tack. Was a NASA engineer. Rambling...

[bamajoey]

There are several Fastenal springs that will greatly improve your trigger. I have 159A springs on three of my CZ's and one of my Brno's. The best of the bunch is the Brno with a 4 oz trigger that passes the bump test with no problem. The CZ's are from 6-10 ozs.

[EddieE]

There are several Fastenal springs that will greatly improve your trigger. I have 159A springs on three of my CZ's and one of my Brno's. The best of the bunch is the Brno with a 4 oz trigger that passes the bump test with no problem. The CZ's are from 6-10 ozs.

As I recall, the 159, 160, 161 were being sold in a case of 100, and I couldn't get them. I'd like to be at about 1 lb...I think I'm at 1.5-2 with the 162. I can live with that for now. I don't think any of the -A springs were available in my local store. Very frustrating paying 12 buck shipping on a $2 spring.

If you have any of the lighter springs laying around, I'd be interested in buying one or two.

[bamajoey]

I seriously doubt I have any remaining, but another thing you may do is take your Fastenal spring to your local hardware store and see if they have an old bin or box with misc. springs. You may be able to find what you want there. We have one that has been there for at least 30 years. I found several springs that I thought might fit, asked what they cost, he said "take them"

[EddieE]

I seriously doubt I have any remaining, but another thing you may do is take your Fastenal spring to your local hardware store and see if they have an old bin or box with misc. springs. You may be able to find what you want there. We have one that has been there for at least 30 years. I found several springs that I thought might fit, asked what they cost, he said "take them"

Thanks for for the tip. They have the -C of the series. So 159-C, 160-C and 161-C are in stock. The only thing I can see is that they are longer. I could cut them to size buy the end that I cut will not longer be "closed". Doubt that makes a difference.

https://www.fastenal.com/products/details/110166655?term=160-c

[Ronnie]

I have installed many no need to shorten at all install and adjust from there.

R

[EddieE]

I have installed many no need to shorten at all install and adjust from there.

R

The OEM spring is 1", the 162-C is 1.75". You installed the 1.75" spring on the CZ?

[Ronnie]

Yes have never changed the length on any fastenall springs.Installed many.Don't know anyone that hasn't got results with their springs .
Have done 455's and 452's
R

[SailDesign]

I have installed many no need to shorten at all install and adjust from there.

R

The OEM spring is 1", the 162-C is 1.75". You installed the 1.75" spring on the CZ?

Hmmm....  Seems like spring-knowledge is missing somewhere here. 

If you shorten a spring, the spring rate INcreases (that's the lbs per inch part) not decreases.    Contrary to popular thinking, but that's how physics works.

So - if you put in a spring with the same wire and coil size, which all the 160's share, then the longer spring, if it fits without binding will have a smaller spring-rate, i.e. will take less effort to squish a particular amount.   BUT - you need the space for that so you don't find the spring compressing to coil-lock (as in cannot compress any more cos all the coils are touching)

Here is the Fastenal spring data chart from their site, which will show you spring-rates (which directly affect trigger weight) with the different lengths, etc.  You may have to download the pdf to see it at any decent size....

Enjoy!  Physics is your friend!

[pdf]https://www.fastenal.com/content/product_specifications/SPR.CMP.M.P.pdf[/pdf]

[painter]

Sail Design is correct.

An important factor not mentioned is pre-load which greatly affects how a spring reacts to force before it starts moving. Once moving the rate takes over.

This is apparent in vehicles where a softer rated longer spring, with excessive pre-load, will feel stiffer/harsher than a more lightly pre-loaded spring with a heavier rating.

How much this is relevant in static trigger spring is way above my pay grade. I 'think' it matters.

[SailDesign]

Sail Design is correct.

An important factor not mentioned is pre-load which greatly affects how a spring reacts to force before it starts moving. Once moving the rate takes over.

This is apparent in vehicles where a softer rated longer spring, with excessive pre-load, will feel stiffer/harsher than a more lightly pre-loaded spring with a heavier rating.

How much this is relevant in static trigger spring is way above my pay grade. I 'think' it matters.

<blush>

The preload factor is what you alter by moving the nut.   All the way down (longer spring) has less weight as it is easier to compress.   All the way up, and the spring is already under compression so you have to match that before it starts moving.

[painter]

Sail Design is correct.

An important factor not mentioned is pre-load which greatly affects how a spring reacts to force before it starts moving. Once moving the rate takes over.

This is apparent in vehicles where a softer rated longer spring, with excessive pre-load, will feel stiffer/harsher than a more lightly pre-loaded spring with a heavier rating.

How much this is relevant in static trigger spring is way above my pay grade. I 'think' it matters.

<blush>

The preload factor is what you alter by moving the nut.   All the way down (longer spring) has less weight as it is easier to compress.   All the way up, and the spring is already under compression so you have to match that before it starts moving.

But the extra length of the longer spring already preloaded to fit in the space available could already feel stronger than the heavier spring with little preload...

I think.

Either way, this is part of the discussion frequently left out of spring talk.

Speaking of spring...I can't wait. The weather is leaving much to be desired in the NE.

[SailDesign]

Sail Design is correct.

An important factor not mentioned is pre-load which greatly affects how a spring reacts to force before it starts moving. Once moving the rate takes over.

This is apparent in vehicles where a softer rated longer spring, with excessive pre-load, will feel stiffer/harsher than a more lightly pre-loaded spring with a heavier rating.

How much this is relevant in static trigger spring is way above my pay grade. I 'think' it matters.

<blush>

The preload factor is what you alter by moving the nut.   All the way down (longer spring) has less weight as it is easier to compress.   All the way up, and the spring is already under compression so you have to match that before it starts moving.

But the extra length of the longer spring already preloaded to fit in the space available could already feel stronger than the heavier spring with little preload...

I think.

Either way, this is part of the discussion frequently left out of spring talk.

Speaking of spring...I can't wait. The weather is leaving much to be desired in the NE.

All of that ^^^     Especially the last one.  RI should have crocuses (croci?) and daffs coming up about now...     Not a danged thang here on my island.

[painter]

We still have about a foot of snow, more in places. While that isn't unusual for here, I'm done with winter.

[EddieE]

Lots of good info here. Thanks. For me, I will stick with the proper length of spring and call it done.

I'm in CT (not far from RI) and the crocuses are up in my yard.