The Firing Line Forums

Go Back   The Firing Line Forums > Hogan's Alley > Handguns: The Semi-automatic Forum

Reply
 
Thread Tools Search this Thread
Old May 12, 2019, 01:12 PM   #26
polyphemus
Senior Member
 
Join Date: June 24, 2012
Posts: 1,048
Quote:
I'm curious what can do this to a magazine spring and how can I avoid it?
My guess would be that the point at which the smaller size spring meets the larger one was weak and that it failed during compression after"quite a few times" of compress/expand cycles.
Regular spring replacement is a prudent rule of maintenance .
polyphemus is offline  
Old May 12, 2019, 01:58 PM   #27
Walt Sherrill
Senior Member
 
Join Date: February 15, 1999
Location: Winston-Salem, NC USA
Posts: 6,289
The Shield magazine only has one spring. But spring failure is the likely source of the problem.

(While I've seen and owned guns that had multiple recoil springs, I don't think I've ever encountered dual springs in a standard single- or double-stack magazine.)
Walt Sherrill is offline  
Old May 12, 2019, 02:15 PM   #28
JohnKSa
Staff
 
Join Date: February 12, 2001
Location: DFW Area
Posts: 22,317
Quote:
Never meant to say you made things up, and no second guess on your intentions either.
To be fair, looking back at your posts, nothing in them implies that I was making things up or that my motives were less than pure and I shouldn't have made it seem like you had.
Quote:
Ejection is job of the extractor and ejector. It doesn't need the magazine follower to kick out the brass.
It's possible that an underlying issue with the extractor or ejector could be masked by the action of the magazine on the extracted brass. The point I was trying to make was that an ejection problem being tied to a magazine issue is possible. In at least some pistols, the design depends on the action of the magazine on the brass for consistent ejection. I don't know if that "feature" is intentional or not.
__________________
Do you know about the TEXAS State Rifle Association?
JohnKSa is offline  
Old May 12, 2019, 04:14 PM   #29
pgb205
Member
 
Join Date: April 11, 2013
Posts: 75
@deputytom. Yep, that is exactly what happened. Both firearm and the magazines were purchased less than 2 years ago.
pgb205 is offline  
Old May 12, 2019, 06:09 PM   #30
kymasabe
Senior Member
 
Join Date: June 10, 2005
Location: SW Florida
Posts: 2,300
Have you considered contacting s&w and see if they'll replace the spring for you. I've contacted them a couple times about the rear sight on my sd9 and they were very helpful, sent parts right out.
__________________
God's creatures big and small, eat them one, eat them all.
kymasabe is offline  
Old May 12, 2019, 09:53 PM   #31
7.62 man
Member
 
Join Date: April 30, 2009
Location: Cyber-world USA
Posts: 35
I have over charged cases & blown mags out of guns & never did that to a mag spring. That had to be done outside the mag because there is not enough room inside the mag to do those turns.
7.62 man is offline  
Old May 13, 2019, 01:52 PM   #32
tipoc
Senior Member
 
Join Date: December 11, 2004
Location: Redwood City, Ca.
Posts: 3,797
Deputy Tom's post #25 shows the problem and the nature of it. It's a weakness in the design of the spring and the mag.

The spring will only do (take on) that right angle kink when released from the mag. Mainly because it can't do it while in the mag. But while in the mag, the smaller diameter of the portion of the spring that is at the top of the mag as it narrows towards the follower can become caught on the larger diameter coil when compressed or as it un-compresses. From the top of the spring the the first 6 coils are about the same diameter. The 7th coil is larger by a bit allowing the 6th to become tangled in the 7th.

Simple thing. The magazine tapers sharply towards the top. The spring must be sized to accommodate this. So one coil can be come caught in the next larger one. The right angle kink only appears when when released from the mag. But notice in the vid that it's caught up inside the mag when he has to pull it out of the mag towards the end of the video.

tipoc
__________________
1. All guns are always loaded.
2. Never let the muzzle cover anything you are not willing to destroy.
3. Keep your finger off the trigger till you are ready to shoot.
4. Identify your target and know what is beyond it.
tipoc is offline  
Old May 13, 2019, 07:56 PM   #33
Walt Sherrill
Senior Member
 
Join Date: February 15, 1999
Location: Winston-Salem, NC USA
Posts: 6,289
Quote:
Originally Posted by tipoc
Simple thing. The magazine tapers sharply towards the top. The spring must be sized to accommodate this. So one coil can be come caught in the next larger one. The right angle kink only appears when when released from the mag. But notice in the vid that it's caught up inside the mag when he has to pull it out of the mag towards the end of the video.
Don't think that really explains what we can see...

I don't think most magazine springs have a taper, (either in shape or metal diameter) which is what you seem to describe. Most of them stay in contact with the sides of the magazine throughout their travel.

If the spring has a defect in the metal and that portion of the spring FAILS while in the magazine, the steel in that area can bend and twist in very unpredictable ways. But because the spring is somethat constrained by the stronger metal case of the mag tube, it can still move around, but is now free to mave in ways the mag tube can't control.

I think the spring twisted and/or kinked due to metal failure, and somewhat knotted itself up inside the mag tube.
  • That knotting and twisting caused the spring to also push against the sides of the tube rather than just the top and bottom, and that in turn caused the follower to be stuck partway down the mag tube -- it sort of expanded (twisted/knotted) and plugged things up and held the follower in an unexpected position. It couldn't do anything else.
When the spring and follower were pulled out of the tube, the spring finally had room to expand farther (from its already screwed up but constrained by the mag tube-shape), and that gave the results we see in the image.
Walt Sherrill is offline  
Old May 14, 2019, 02:17 AM   #34
tipoc
Senior Member
 
Join Date: December 11, 2004
Location: Redwood City, Ca.
Posts: 3,797
Watch the video.

Remove the spring from the mag and lay it alongside the mag.

tipoc
__________________
1. All guns are always loaded.
2. Never let the muzzle cover anything you are not willing to destroy.
3. Keep your finger off the trigger till you are ready to shoot.
4. Identify your target and know what is beyond it.
tipoc is offline  
Old May 14, 2019, 07:35 AM   #35
polyphemus
Senior Member
 
Join Date: June 24, 2012
Posts: 1,048
Quote:
I don't think most magazine springs have a taper, (either in shape or metal diameter)
Whether most magazines don't have different diameter springs,OP's happens to
have one that that does.Metal fatigue can cause the smaller D.section to collapse into the larger one and when removed show the 90* bend visible in his
photo.MecGar magazines also have smaller D. top loops to fit in the step follower.
polyphemus is offline  
Old May 14, 2019, 12:09 PM   #36
tipoc
Senior Member
 
Join Date: December 11, 2004
Location: Redwood City, Ca.
Posts: 3,797
Below you can see the mag and spring from a 9mm Shield. Note the change in diameter (or size of coil) of the spring 6 coils down. this creates the possibility of one coil getting trapped in another in rare circumstances.



tipoc
__________________
1. All guns are always loaded.
2. Never let the muzzle cover anything you are not willing to destroy.
3. Keep your finger off the trigger till you are ready to shoot.
4. Identify your target and know what is beyond it.
tipoc is offline  
Old May 14, 2019, 12:35 PM   #37
tipoc
Senior Member
 
Join Date: December 11, 2004
Location: Redwood City, Ca.
Posts: 3,797
Quote:
Whether most magazines don't have different diameter springs,OP's happens to
have one that that does.Metal fatigue can cause the smaller D.section to collapse into the larger one and when removed show the 90* bend visible in his
photo.MecGar magazines also have smaller D. top loops to fit in the step follower.
Metal fatigue is a possibility. Incorrect assembly another. This would be with the recoil spring inserted backwards by an inattentive individual.

Below are the 7 and 8 round mags side by side. Same spring in both and identical follower.



tipoc
__________________
1. All guns are always loaded.
2. Never let the muzzle cover anything you are not willing to destroy.
3. Keep your finger off the trigger till you are ready to shoot.
4. Identify your target and know what is beyond it.

Last edited by tipoc; May 14, 2019 at 12:43 PM.
tipoc is offline  
Old May 14, 2019, 12:57 PM   #38
tipoc
Senior Member
 
Join Date: December 11, 2004
Location: Redwood City, Ca.
Posts: 3,797
Both the length of the coils and the width of the coils are different. The length of the longer coil being 1.125" vs. .900 for the shorter coil. The width being .510 for the longer vs. .365 for the shorter. This allows for the one to nestle comfortably in the other when compressed. Also allows for one to hang up on the other in rare circumstances.

This is not a common occurrence. It's never happened to me. But clearly it happens.





tipoc
__________________
1. All guns are always loaded.
2. Never let the muzzle cover anything you are not willing to destroy.
3. Keep your finger off the trigger till you are ready to shoot.
4. Identify your target and know what is beyond it.
tipoc is offline  
Old May 14, 2019, 03:49 PM   #39
pgb205
Member
 
Join Date: April 11, 2013
Posts: 75
@tipoc. So here is the thing. I remember disassembling and cleaning several of my magazines a while back. Don't remember if this mag was one of those worked on, but it's entirely possible.

When you say "recoil spring inserted backwards" do you mean up/down or left/right dimension was not correctly setup?
pgb205 is offline  
Old May 14, 2019, 05:03 PM   #40
tipoc
Senior Member
 
Join Date: December 11, 2004
Location: Redwood City, Ca.
Posts: 3,797




In the pic above, the spring above on the left, the top of the spring, the highest point, is in the correct orientation in relation to the follower and in relation to the mags. They have a forward orientation. The top faces forward, towards the front of the mag.

These springs have a big bottom and a smaller top. There is only one way to get them in the mag in that regard. The smaller end goes in first.

Like the magazine, the springs have a top and bottom and a front and a back. The top of the spring faces forward.

They is only one way to get them wrong and still fit in the mag body...the front of the spring is inserted incorrectly when it faces backward, towards the rear of the mag.

The spring on the right faces backward, the front faces the rear of the mag and the rear of the follower. A person could force them in this way. It would be clumsy to do but it could be done.

That would maybe cause another issue. See the pic below. When these springs face forward they are flat on the right hand side. Meaning that when placed flat on a flat surface only the right hand side lays flat. This means that the smaller portion of the springs is not centered to the main body of the spring. This won't make much difference in actual practice. But if you have it in backwards it might make it more liable to kink.



tipoc
__________________
1. All guns are always loaded.
2. Never let the muzzle cover anything you are not willing to destroy.
3. Keep your finger off the trigger till you are ready to shoot.
4. Identify your target and know what is beyond it.

Last edited by tipoc; May 14, 2019 at 05:14 PM.
tipoc is offline  
Old May 14, 2019, 05:18 PM   #41
JB60
Member
 
Join Date: December 14, 2016
Location: Alabama
Posts: 52
Kinked springs I've had two of them , I read on S&W forums couple years ago of defective Shield mag springs . One of mine may have been reassembling the spring backwards , Wolff Springs sells heavier springs pack of three 7 and 8 round are the same size
JB60 is offline  
Old May 14, 2019, 08:31 PM   #42
Walt Sherrill
Senior Member
 
Join Date: February 15, 1999
Location: Winston-Salem, NC USA
Posts: 6,289
Quote:
Originally Posted by Polyphemus
Whether most magazines don't have different diameter springs,OP's happens tohave one that that does.Metal fatigue can cause the smaller D.section to collapse into the larger one and when removed show the 90* bend visible in his
photo.MecGar magazines also have smaller D. top loops to fit in the step follower.
I stand corrected on diameters varying, etc. Nearly all of the mag springs I've seen have been pretty uniform in size, and almost never find the diameter of the wire changing. (That would take a really unusual production process, and one that had to be created as the wire itself was formed; bending the wire differently as the spring is shaped around a form would be less complicated.)

If the spring has defective metal it can bend or kink in ways that a structurally sound spring can't and you'll end up with a strangely deformed or kinked spring that bends in ways that it wasn't intended to bend. It could look exactly like the first photos posted in this discussion.

I don't see that the wire diameter has really changed (which was what I thought the various folks were referring to) in the photos here, but do see the shape and the length of some of the segments changing from one end to another. But even that is unusal and not all that common.

Last edited by Walt Sherrill; May 14, 2019 at 08:36 PM.
Walt Sherrill is offline  
Old May 14, 2019, 08:36 PM   #43
Onward Allusion
Senior Member
 
Join Date: November 17, 2009
Location: IN
Posts: 2,711
The 17 round 59 series Mec Gars have a similar tapered spring design. It allows the spring to fold into itself and hold a couple more rounds than the OEM S&W mag. I had experienced binding problems after the spring is worn. I think the OP's experience was caused by spring design and fatigue.
__________________
AI + Quantum Computing = Human Extinction Event
Onward Allusion is offline  
Old May 15, 2019, 10:38 AM   #44
tipoc
Senior Member
 
Join Date: December 11, 2004
Location: Redwood City, Ca.
Posts: 3,797
The diameter of the wire doesn't change, Walt is right there. But the size of the coils does. I called them the diameters of the coils because I don't recall the proper nomenclature.

If this was a common problem it would have been all over the internet some years back so it may be a result of spring fatigue and/or incorrect assembly.

tipoc
__________________
1. All guns are always loaded.
2. Never let the muzzle cover anything you are not willing to destroy.
3. Keep your finger off the trigger till you are ready to shoot.
4. Identify your target and know what is beyond it.
tipoc is offline  
Old May 15, 2019, 11:25 AM   #45
Onward Allusion
Senior Member
 
Join Date: November 17, 2009
Location: IN
Posts: 2,711
Diameter of spring wire = gauge or thickness (in mm or inch). Spring Diameter = Outer Diameter and Inner Diameter

Typical life of a garage door spring is like 10,000 cycles. Even if the life of a mag spring is 500 cycles, that would be like over 5,000 rounds down the pipe with a single mag.
__________________
AI + Quantum Computing = Human Extinction Event
Onward Allusion is offline  
Old May 15, 2019, 12:29 PM   #46
polyphemus
Senior Member
 
Join Date: June 24, 2012
Posts: 1,048
Perimeter if you want to be precise in its geometry,there's probably no need for that.
polyphemus is offline  
Old May 15, 2019, 07:15 PM   #47
pgb205
Member
 
Join Date: April 11, 2013
Posts: 75
emailed sw. they will be sending me a replacement spring for this magazine.
I have probably put quite a few rounds (1000+ at least) through this magazine, maybe even didn't install the spring in correct orientation (just a theory).

Still very concerning to have such a sudden and massive failure on what has been my
CCW weapon for several years.
pgb205 is offline  
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 09:17 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2018 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.08838 seconds with 11 queries