Help me with spring weight

[chrisemt]

This is kinda out of my lane but here goes.

I just got a G34 and want to play around with the different spring weights. I've read a few threads here on GT and at CGR regarding different weights but still don't have a grasp on the idea.

If I put a 13 lb recoil spring on a guide rod, what should I do to the trigger spring and the firing pin spring? Should all the springs be "reduced" power or is there a better combination? I am not looking at changing the safety plunger spring.

This will be for IPSC or IDPA and general shooting at the range not for carry purposes of course.

If you don't want to divulge your secret setup on the board, PM or email me.

Thanks

-Chris

[Yar]

I run a 13# ismi recoil spring, tungsten guide rod, reduced power striker spring, and glockmeister competition trigger spring for 9mm. Match that with a 124 grain 9mm going 1050 fps (130 pf minor), or 1200 fps (open minor steel load).

[Bamboozled!!!]

Originally posted by chrisemt
If I put a 13 lb recoil spring on a guide rod, what should I do to the trigger spring and the firing pin spring? Should all the springs be "reduced" power or is there a better combination? I am not looking at changing the safety plunger spring.



Chris-

If you go with a significantly lighter recoil spring, such as the 13# you mentioned, you should install a reduced power striker spring. If you don't, your 34 could unlock pre-maturely during the firing cycle. And as you probably know, this can cause problems.

The reason is in the Glock, the recoil spring and striker spring work in opposition to each other. As you pull the trigger to bring the striker to its fully rearward position (just before the striker releases), the striker spring is working to move the slide rearward. If the recoil spring is not strong enough to hold the slide closed, the slide/barrel will begin to unlock. You can see this most clearly if you remove your recoil spring assembly and re-assemble your pistol. Note that your slide is being held out of battery by the striker spring.

Once you install a reduced power recoil and striker springs, you can check for proper function of your pistol by:
1. Ensure the pistol is unloaded and magazine is out of the weapon.
2. Double check to make sure the pistol is unloaded.
3. Point the pistol straight up and slowly pull the trigger. Make sure that your slide does NOT move rearward during the trigger squeeze. If not, your good to go. If it moves, then you need either a heavier recoil spring or a lighter striker spring.

As for the other springs, an extra power trigger spring will help lighten your trigger pull, because it essentially helps you pull the trigger bar rearward. A reduced power firing pin plunger spring will make the 1st stage (take-up) of your trigger stroke a little lighter and smoother.

I hope this helps.




Addendum:

FWIW - I run a 13# ISMI recoil spring on the stock guide rod with the above mentioned springs, a Ghost Rocket 3.5# connector, and a basic polishing of components. I have not measured the trigger weight, but it is significantly lighter/smoother than my G34 when stock.

FYI, the Wolff competition spring kit for Glock is available from Brownells.
http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=22867&title=TRIGGER+GROUP+COMPETITION+PAK+for+GLOCK%7e&s=48734#48734

Update:
Unfortunately, they are currenly out of stock. But, I'm sure Matt from CGR can help you out.

[Bamboozled!!!]

Consolidated this post in the above addendum.

[Custom Glock Racing]

I dont recommend changing the trigger spring. To run very light recoil springs you may need to run the 4lb firing pin spring. The only way to know though is to try it out.

[Mtrclass]

Some Glocks when running light recoil springs will have a problem with the slide moving rearward when the trigger is pulled. The reason for this is the striker spring and the recoil spring work against each other. In other words if the pressure required to push the striker to the rear is more then the pressure of the recoil spring holding the slide assembly forward while the gun is in battery, the slide will more rearward. This can cause several problems.

If you are having this problem you can go to the lighter (4 lbs) striker spring, balancing the spring pressures again, and this should eliminate the problem. If you do go with the lighter striker spring you are reducing the available energy to the striker to impact the primer creating potential problems with light hits. When I use a light striker spring I always use a non-lightened striker to help eliminate this problem.

I don't recommend using a lightened trigger spring because this tends to cause the trigger to reset slower ( as well as potentially cause other problems)especially if the gun is dirty. As your skill level increases you are going to want the trigger to reset as quickly as possible, because this must occur before your can fire the next shot.

Depending on the school of thought you come from you should be looking at a couple of different things when you modify your trigger assembly. The most common goal is to reduce the pull weight followed closely by smoothing up the pull across it's length. And often overlooked goal is to reduce the length of the pull and the length of the reset. On my triggers I am more concerned with pull length and reset length then the overall lightness of the pull. I have found that these items tend to improve my splits and accuracy more then having the lightest trigger pull. Everyone always refer's to the 1911 when discussing triggers, normally stating that they have the best triggers because of how light they can be made. But it is also the extremely short length of pull AND reset that make them work so well for high speed competitions.

Just my 2 cents worth............

[chrisemt]

Thanks for the education so far fellas.

I ordered a 13lb ISMI recoil spring, metal guid rod, and the reduced power trigger and firing pin springs. I will try out different combinations and see what I like.

I love being able to work on the GLOCK platform without special tools or having to attend armorer class.

-Chris

[shootingbuff]

Listen,

I may be nobody but Matt of CGR is da-man. Might want to take note of what he posted above since it didn't seem to take the first time.

sb

[chrisemt]

Originally posted by Custom Glock Racing
I dont recommend changing the trigger spring. To run very light recoil springs you may need to run the 4lb firing pin spring. The only way to know though is to try it out.

Using the regular 4# firing pin spring will reduce the chances of light primer strikes?

Out of 100 rounds, I had 1 light primer strike today but didn't put the 4# spring back in.

-Chris

[Bamboozled!!!]

Originally posted by chrisemt
Using the regular 4# firing pin spring will reduce the chances of light primer strikes?

Out of 100 rounds, I had 1 light primer strike today but didn't put the 4# spring back in.

-Chris


Chris,

Using the reduced power striker spring (4#, factory is 5.5#) can increase the likelihood of light primer strikes. Is the light primer strike well centered, or is it off center? Are you using factory ammo or do you reload? If you reload, using Federal primers may improve ignition as they have the reputation of being more sensitive than other brands. CCI primers have the reputation of being the least sensitive.

[Custom Glock Racing]

It is also very important to make sure you properly seat your primers, they should about .003 under flush

[Bamboozled!!!]

Originally posted by Custom Glock Racing
It is also very important to make sure you properly seat your primers, they should about .003 under flush


Yeah, what he said...

[chrisemt]

I don't reload yet (it's on the Christmas list) but thanks for the tips about the pimers.

It was factory ammo and the primer strike was right in the center.

Thanks fellas

-Chris

[Custom Glock Racing]

What factory ammo exactly?