Question about cutting coils off recoil springs

[proraptor]

So I have an ISMI 13 lb recoil spring on a Lone wolf stainless guide rod in my G17. My understanding is cutting 1-3 coils (depending on the gun) will improve extraction. Is this correct?

If so should I start by cutting one coil off and testing and cutting off more if I feel the need to do so? Or is there a secret # of coils to cut off that should work with every glock?

Thanks guys

[Chris Keen]

I don't advocate cutting ANY coils. Stick with a stock spring. Change it when you have issues that seem to be related to feeding.

If you are having extraction problems, then maybe there's something really wrong. Have you detail cleaned the gun lately paying close attention to the extractor?

[proraptor]

Im not having extraction problems but the brass isnt flying far out of the gun like it used to. I wont go back to the stock spring cause the 13 lb ISMI makes the muzzle flip calm down a lot...

I detail strip the gun every time I shoot pretty much to check everything out....The only thing that has changed is the recoil spring. Ive also read that cutting coils off the spring will eject brass farther

[Flexmoney]

I wont go back to the stock spring cause the 13 lb ISMI makes the muzzle flip calm down a lot...

So does a good grip and stance.

[proraptor]

I wont go back to the stock spring cause the 13 lb ISMI makes the muzzle flip calm down a lot...

So does a good grip and stance.

I have a good grip and stance and you know what the spring still helped.....Guess Ill have to resort to glock talk to answer my question

[SA Friday]

If you are getting reliable lock-up and cycling from the 13lb spring uncut and the brass is ejecting vs dribbling down your hand, you are golden. No need to cut coils unless you are getting failures to eject and hot brass dribbling down your hand when it does eject.

Cutting coils changes the compression ratio and can help with ejection, but it better to not if possible. The uncut spring will last longer and be a more reliable shooting gun.

Another option is to bump up your pf a little. The more I shoot, the more I am in favor of this option with my glock production guns. More reliable all around, and it pisses me off when steel doesn't fall with a slightly low hit

[HoMiE]

What PF are you shooting? It doesn't matter how far the gun throws the brass like SA said. Going from stock to 13# recoil spring, the gun will throw it less(I think you meant ejection, not extraction). I've never used the LW guide rod and I can't find the topic, but there was a topic where some guide rods are too big to use with ISMI springs. Are you sure the recoil spring isn't binding up?

[David Sinko]

I remember seeing a stock captured guide rod assembly where the middle portion of the spring was thinned down and reduced in diameter. If I recall, this was supposed to keep the muzzle down while cycling yet still give a strong return to battery. Does this really accomplish those objectives and how do you modify the spring in this manner?

Dave Sinko

[PJONES5]

I wont go back to the stock spring cause the 13 lb ISMI makes the muzzle flip calm down a lot...

So does a good grip and stance.

I have a good grip and stance and you know what the spring still helped.....Guess Ill have to resort to glock talk to answer my question

:ph34r:

PAT

[Flexmoney]

So I have an ISMI 13 lb recoil spring on a Lone wolf stainless guide rod in my G17. My understanding is cutting 1-3 coils (depending on the gun) will improve extraction. Is this correct?

Well...let me try this again. Maybe I can be nicer.

Will it improve extraction? No.

Will it improve ejection? No...yes, conditionally.

Does your gun have a comp hanging on the end of the barrel? Are you using low powered ammo? Are you of a physically slight build?

If a shooter has some of these issues, then they need to take them into account. If not, then my experience tells me that the shooter could likely use some work on their grip and stance.

I run my Glock 9mm with a stock rod and spring and 135 power factor ammo. I can understand that shooters want to go with a lighter recoil spring for feel. If your are having trouble with function, however, then identifying the source is important.

[Flexmoney]

I remember seeing a stock captured guide rod assembly where the middle portion of the spring was thinned down and reduced in diameter. If I recall, this was supposed to keep the muzzle down while cycling yet still give a strong return to battery. Does this really accomplish those objectives and how do you modify the spring in this manner?

Dave Sinko

Dave,

The way to do that would be to turn the spring (while on the rod) as in a lathe. Then, apply a file or such to remove material.

It always seemed to me that this idea would mean less force at lock-up (not one of my favorite things on the glock...as pulling the trigger works to unlock the gun).

[Woody Allen]

So I have an ISMI 13 lb recoil spring on a Lone wolf stainless guide rod in my G17. My understanding is cutting 1-3 coils (depending on the gun) will improve extraction. Is this correct?

If so should I start by cutting one coil off and testing and cutting off more if I feel the need to do so? Or is there a secret # of coils to cut off that should work with every glock?

Thanks guys

Alot of shooters use the 13lb with a G34 and cut off three or four coils to improve reliability with match loads, i.e., 129-134 pf loads. I will have extraction/ejection issues sooner with a stock 13lb than one with 3 coils removed. So, yes, my experience has shown that removing the coils improves extraction/ejection and prolongs the usable life of the spring. I like the 13lb spring, I like my match loads, and it all works much better with three coils cuttoff the spring. Apparently, I am not the only one who espouses this viewpoint.

Take a look at: http://www.custom-glock.com/springtech.html

Edited January 11, 2008 by Woody Allen

[proraptor]

So I have an ISMI 13 lb recoil spring on a Lone wolf stainless guide rod in my G17. My understanding is cutting 1-3 coils (depending on the gun) will improve extraction. Is this correct?

If so should I start by cutting one coil off and testing and cutting off more if I feel the need to do so? Or is there a secret # of coils to cut off that should work with every glock?

Thanks guys

Alot of shooters use the 13lb with a G34 and cut off three or four coils to improve reliability with match loads, i.e., 129-134 pf loads. I will have extraction/ejection issues sooner with a stock 13lb than one with 3 coils removed. So, yes, my experience has shown that removing the coils improves extraction/ejection and prolongs the usable life of the spring. I like the 13lb spring, I like my match loads, and it all works much better with three coils cuttoff the spring. Apparently, I am not the only one who espouses this viewpoint.

Take a look at: http://www.custom-glock.com/springtech.html

Exactly what I was looking for thanks

[bountyhunter]

Im not having extraction problems but the brass isnt flying far out of the gun like it used to. I wont go back to the stock spring cause the 13 lb ISMI makes the muzzle flip calm down a lot...

I detail strip the gun every time I shoot pretty much to check everything out....The only thing that has changed is the recoil spring. Ive also read that cutting coils off the spring will eject brass farther

Most of the newer recoil springs are "progressive" in that the spring constant is not uniform. If you snip a progressive spring from the end, you don't make it linearly softer, but you do change the way it works.

If it's a linear spring, here is the "secret":

To reduce the spring force by 10% you do NOT NOT NOT shorten the spring by 10% of it's total free length.

You measure the LENGTH OF COMPRESSION and reduce the free length by about 10% of that. In other words, if you have a spring that is 6" long (free length) and is compressed down to 3" in use, that means it is being compressed 3". You will reduce the spring's compressed force by about 10% if you snip about (10% x 3) = 0.3" off of it.

[bountyhunter]

It always seemed to me that this idea would mean less force at lock-up (not one of my favorite things on the glock...as pulling the trigger works to unlock the gun).

Good point. I never noticed that.

[David Sinko]

I agree with Mr. Flexmoney that grip and stance are the key, especially with the Glock. As a lifelong hardcore revolver shooter, I have always been able to get away with somewhat sloppy grip and stance, in a pinch. The revolvers always worked properly and I never had any problems. When I started shooting these Glocks I realized immediately how important it is to grip the gun properly. The only problems I've ever had with a Glock have always been with ejection and I'm sure it's my fault because I'm not gripping the gun hard enough. The stock spring does seem a bit heavy though when shooting 135 PF in my 35. I'm trying to find the best compromise but every modification will have some kind of consequence. And I grudgingly admit that my 35 is more reliable than a revolver with a "Federal primer only" action job.

Dave Sinko

[BR]

Im not having extraction problems but the brass isnt flying far out of the gun like it used to. I wont go back to the stock spring cause the 13 lb ISMI makes the muzzle flip calm down a lot...

I think it may be an ammo issue, as opposed to gaining a benefit by cutting coils off your recoil spring. You need to tune a lightened recoil spring to your minor pf ammo. I tried some of my buddy SA Friday's old (2 or 3 years ago) 128 pf loads in my G34 with a regular uncut 13lb. ISMI spring, and the brass, most of the time, just dribbled out. Hated it. I still use the full 13lb spring, but load my ammo to 138pf, and now the brass kicks out great and poppers drop fast. I can't think of any advantage to cutting the spring. Just my $.02. Cheers.

-br

Edited January 12, 2008 by joker22

[SA Friday]

Custom tuning a glock to shoot a competition reload cartridge can make a difference. I cannot deny this one bit. I have four glocks customized, and I shoot three of them in USPSA. Glocks are not made to shoot a low pf round. They are built primarily for defensive shooting of defensive ammo, and so can require some tinkering to get them to run reliably, but there are options in many instances. Shooting a G35 with a 135pf round and the stock recoil spring I would suspect might not have the most reliable ejection. Shooting a G34 or G17 with a 130pf round (using a 147gr bullet) is down right difficult to get to run reliably. Going lower in recoil spring weight does help a lot. So does grip and stance, but I cannot say without a doubt one is the cure-all and the other is not. IMO, both play a significant factor in getting YOUR gun to run for YOU.

The other side of this is modifying the gun to get a perceived better running gun and disregarding the potential trade-off of reliability and safety. Secondly, the potential frustration with a beginner's grip and stance issues causing failures can result in unecessarily changing to another gun or god forbid quitting USPSA all together. The downsides to not modifying a glock to shoot competition ammo and the downsides to not learning proper grip and stance are both unacceptable IMO. Accepting one of these options as gospel as an overall cure to ejection problems is even worse than unacceptable, its...well...dumb.

If modifications didn't make guns easier to shoot, nobody would do them.

If proper grip and stance didn't affect the guns reliability and accuracy, nobody would care about it.

[HoMiE]

I keep waiting to see someone reply with...

"SHOOT THAT TOOL!"

I admit, when I started out, I wanted to tinker and do this and that to my gun. But no matter what I did to it, I didn't start to shoot better until I started to pay attention to those things that sit on top of the slide.

[Woody Allen]

Shooting a G34 or G17 with a 130pf round (using a 147gr bullet) is down right difficult to get to run reliably.

I disagree. Nothing difficult about it. (1) Lighter recoil spring-13lb ISMI with a few coils cut off-change it out every 5K to 10K rounds. (2) Wolff competition striker spring. (3) Glock factory trigger spring. (4) LW 3.5 connector. (5) LS lightened steel striker. Make sure the striker channel is kept clean. 100% reliability-just gotta change the springs out more often than you would with stock springs.

[SA Friday]

Shooting a G34 or G17 with a 130pf round (using a 147gr bullet) is down right difficult to get to run reliably.

I disagree. Nothing difficult about it. (1) Lighter recoil spring-13lb ISMI with a few coils cut off-change it out every 5K to 10K rounds. (2) Wolff competition striker spring. (3) Glock factory trigger spring. (4) LW 3.5 connector. (5) LS lightened steel striker. Make sure the striker channel is kept clean. 100% reliability-just gotta change the springs out more often than you would with stock springs.

within the context of the original post, this would be an unmodified glock.

[proraptor]

The load Im running is about a 132 pf....Maybe Ill bump it up a bit....

[border]

Having a few extra recoil springs around to play with won't cost much. Clip one and try it to see how it reacts to your personal load and PF. If you like what you see and feel you're done. Finding the right load/bullet for the PF you want to shoot and having the Glock run reliably for match work with that combo is paramount. I think we sometimes (well, ...me), forget that they were originally designed for military/police use. We've hot-rodded them to be what we want. But that's how we learn...that's what makes it personal and therefore fun...For me stock recoil in my 34 does everything I want it to do.

[Aircooled6racer]

Hello: I cut 3 coils off my ISMI 13lb Glock spring and it works perfectly everytime. The load for my G35 is around 137PF and the load I used to use in my G34 was 131PF. The same spring in both. I found the spring would go into coil bind at full length. With 3 coils cut off it just works. So go cut 3 coils off and have a drink ;-). Thanks, Eric

[Flexmoney]

I found the spring would go into coil bind at full length.

That was my next question. Bind would address the desire that seems to be out there to chop these springs down. I haven't tried any ISMI springs as of late.

Can you expand a bit on what you found?