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Any ideas on this Spring problem?

5K views 37 replies 16 participants last post by  btrogdon 
#1 ·
in an earlier thread, I talked about the difficulty I had in racking the slide on a new Shield. I ran over 600 rounds through it to no avail. I decided to contact S&W for advice. They sent a new spring. I installed it. It was worse.

So I took it back out again. This is what it did as I took it out. This is a brand new spring that was compressed on installation, and was compressed a couple of times trying to get the slide to lock back.

Can I just push the spring back onto the guide rod? Is it broken, or can I use it once I get it back onto the rod (if that's possible)?

Frustrating -- but S&W responded quickly. In looking at the old spring, It appears that the only thing that holds it in place is the slight detent at the end of the rod. There appears to be no other parts. Interesting.
 

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#5 ·
That's exactly what I thought , too, but neither the new recoils spring nor the original have any sort of snap ring to hold things in place. I could probably twist the original spring a bit and have it pop right off, too (but I won't).

I'm determine to get to the bottom of this. The little gun is otherwise perfect, and I really like it. I refuse to let a silly spring undermine my satisfaction. I know S&W can come up with a solution if I can raise the issue to the right place.

I'm attaching some other photos as requested. I've stared at this for several days, and I'll be darned if I can see anything wrong. Once again, the slide, minus the recoil spring and barrel, moves back and forth on the lower frame like warm butter. You could not want it to be smoother. But when you put the barrel and spring back in, it hangs up a bit when the slide first starts to move, then it moves smoothly back till the notch for the slide stop is almost over the stop lever. Then I have to push it against the desk or the workbench to get it to move the rest of the way back. There is something in that last few centimeters that acts like it is dragging. But I can't find a scratch on anything to indicate where. Unfortunately, I cannot remove the secondary spring to look inside that rod. I suspect that the issue is in that part of the mechanism.
 

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#4 ·
I've been somewhat following your threads on the problem you've been having. Something definitely doesn't seem right. Is there a chance you could take some more pix of the underside of the slide with and without the guide rod installed, focusing on the area where the the guide rod sits at the end of the slide as well as where it rests on the barrel lug? I may suspect the pocket in the slide where the guide rod goes may not have been counter sunk deep enough causing the springs to be over compressed and not allowing the slide to go back the way it should without a lot of effort. We have to assume that both of your guide rods have been correct at this point, so it must be something else. I could be way off base here, but it wouldn't hurt to rule it out huh? I myself would send it to S&W with a detailed description of the problem with it and what you've tried. Maybe a gunsmith on the forum will be along soon that has experience with this problem to save the day. I hope you find resolve soon and keep us posted.
 
#6 ·
ok.. the only thing different that I can see is that when my slide is locked back, my guide rod sticks out past the frame about 3/32" whereas yours looks flush at the end in your picture. I can't tell from the angle of the pic though. My guide rod has no snap ring. Looks like the flat spring is just twisted onto the rod with a tighter coil at the end to keep it from popping off the end. I imagine that over compressing the coil would cause it to enlarge and slip off though.
 
#7 ·
Thanks Citizen -- both of the recoil springs fit flush on the front of the slide. The new spring just popped off of the rod. I think you are right on the spring. It doesn't look like there was any thought of a spring retainer. It is just twisted tighter so that the end of the spring forces its way I=under the end of the secondary spring rod. I suspect that the new one was not tightened enough at the end. I made a little oak gadget to compress it back enough to put it back on the guide rod, but its still loose enough that if I were to use it, I believe it would pop off again the next time I pulled it out for cleaning. It was a lot of "fun" figuring out how to compress the spring enough to get it back on the rod. that spring is a hard little bugger to compress.

Its kinda funny, though. Throughout my life, I have often grown to like the things that have made me work to like them (take my daughter for instance -- or worse, the Lotus Europa that hardly ever brought me back from where it took me to). This little problem is a pain, but it hasn't caused me to dislike the gun one bit. I don't like its spring very much, and I truly hope that S&W or someone (APEX??? Wolff???) will redesign it and make it a good one some day. When they do, I'll put one on this gun. It'll still be here.
 
#8 ·
I very much like my Shield .40, but this "captive" (captured?) guide rod assembly leaves a lot to be desired. I always pinch the last coil before the muzzle-end flange with a pair of needle nose pliers before re-assembly. I also would be interested in a better solution. Your slide looks identical to mine internally.
 
#9 ·
I don't have any answers. I own 3 Shields and used to own 4 until I gave the some one of his own. None have been extremely hard to rack the slide on, even when new. All slides have loosened up a bit with use. It makes me wonder if it may be a slide to frame fit it you have pretty much exhausted spring issued? I would send it back to Smith. You may have gotten a lemon. For what it's with, several of my shooting buddies have Shields also and love them. I am going to subscribe to your posts and follow this. I am real curios also.
 
#13 ·
The spring that I posted at the beginning of this thread is the new spring that S&W sent. It was captured only by the space between the silver guide rod and the black one. But the first time I took it out of the gun after having installed it, it popped off the guide rod and wound up like it looks in the picture at post 1. The original spring still remains intact, but it is the one that seems to be causing the issues with racking it. The "new" spring that S&W sent only was installed, I racked the slide a couple of times. Then I took the gun down to put a little oil on the slide hoping to get started on the break-in of the new spring. But when I pulled it out, it "popped" and the spring would up being un-captured. It was a bear to get back under compression, and I have little trust in that spring now.

Keep in mind -- this is NOT an "I hate my Shield" thread. I like it a lot. I just want to be able to rack the slide like I do with my other guns. Having to push the slide against a table or something to get the slide all the way back is just not right. I've handled other Shields. They do not do this.
 
#14 ·
And S&W has acted honorably. They sent me a new spring immediately when I contacted them, but the new spring that they sent wound up coming apart. I am at the point that I think I'm going to ask S&W to look at it to see if there is a problem that they can identify.
 
#22 ·
I talked with S&W, a mailing label is on the way (they say 7 days to e-mail one -- I presume they are scheduling arrivals).

I sent a note to Apex who responded that their development folks have not looked at the Shield recoil spring. Perhaps I planted a seed -- who knows?

I haven't figured out how best to contact Wolff yet, but I will.

But its likely that my little gun will come back from S&W with its problem solved. I hope, as long as they don't mess with its accuracy.

I will say again, I really like this little gun, and I'm going to do whatever it takes to get its spring issue resolved.
 
#23 ·
Shield spring

You are not alone, I bought one yesterday the test shell is from late March, it is so hard to lock back that its almost impossible to do so. Field stripping and reassembly is a major project. I have 4 other M&P's with no issues. I know short slides need heavy springs but this is just crazy. I am going to check out a couple of friends guns before I call S&W.
 
#24 ·
You are not alone, I bought one yesterday the test shell is from late March, it is so hard to lock back that its almost impossible to do so. Field stripping and reassembly is a major project. I have 4 other M&P's with no issues. I know short slides need heavy springs but this is just crazy. I am going to check out a couple of friends guns before I call S&W.
I tried several Shields before buying one. All of them were very smooth. None had the issues that I have run into with mine. None of my other <&Ps behave this way, and my little Sig P938 has a much shorter slide length, but it is the easiest of all to rack. I suspect that S&W got a batch of non-spec coils from somebody.
 
#27 ·
I also purchased a new shield 9 at the end of march. Manufacture date was 3/20. It was very hard to rack to get the slide back all of the way. It was easy for the first part, the outer spring, I assume. When I hit the second stage spring, it was like a wall and didn't want to move any further.
I finally got it back and was able to field strip it. The head of my RSA was bent over to the side. It was new out of the box from a shipment my dealer just got in. The bend didn't seem to be affecting the spring in any way, it was just weird. The second stage was still very tight.
I put some lube on the RSA where the inner spring goes into the tube and let it drip toward the back. Reassembled and racked it a few times. it loosened up nicely after that. It is like the inner spring is dry and scraping on the outer tube. I am still going to ask S&W to replace it because of the bent head.
 
#28 · (Edited)
I tried letting some MC2500 dribble down the guide rod, and it did help it quite a bit, until I sent 50 or 60 rounds through the gun. By then, it was back to being stiff and sort of scratchy. It has now developed a new trick. I can move it to where the slide stop is just about to pop into its groove -- then if I release the slide slowly, it will stay where it is for just a second or two before it slingshots back. Its as if there is some sort of constriction inside the secondary spring's guide tube. The outside of the tube is smooth as glass, not a hint of a ripple or anything inside it.

The flat part of the guide rod end that goes up against the lug does not appear to be bent, but it is all scratched up. I've no idea how or when that happened and I can't see that it makes any difference. I stood the spring up on its end and held it up against a drafting triangle to see if I could detect any bends in the guide, but there are none that I can see.

I'm meeting a guy tomorrow to borrow a recoil spring from a known good Shield to see what his spring does in my gun. I cannot imagine that its anything other than the secondary spring and/or its guide rod. I'm trying to envision what the need for a two stage spring might be, and why the secondary spring seems to be so very much stiffer than the primary flat spring. Of course, I have no way to measure the rates for either spring, but it sure appears that the secondary spring is a stiff little bugger.

I am going to get to the bottom of this.

I sent emails to several suppliers of custom recoil springs. A few have responded. Most have said they couldn't help, but several said that they have been getting a lot of calls for a Shield spring and that they were looking into it.
 
#31 ·
Well, its on its way back to SAW (that's what is says on the FEDEX label). I'm sure curious to see what they find. I hope they find something easy to fix. I really like this little gun. I already am having second thoughts about sending it in. Maybe I should have put it in the closet till a Wolff Spring was available. Oh well......

I just read the thing about warped BG.380 frames. That's frightening. I'm scared to death that whatever the mothership does will mess up its accuracy. Arrrghhhhh!!!!
 
#32 ·
hey jwh321:
i`m a newbie on here but might be able to offer some help. i own a shield 9 and have the same issue, on my 2nd recoil spring. my 1st one went all the way across the garage when it came apart, quite a shock because i wasn`t expecting that. when the spring is installed it drags on that U shaped piece of metal S&W decided to install for whatever reason. the other thing is that the spring ID is too big for the tube it rides on, hence the snaky type fit. i used a black marker and coated the edge of the entire spring AND the U shaped metal piece and then racked the gun about 50-60 times and then took it apart and voila, there were shiny marks on a few coils of the spring AND the U. just my $.02 worth. build date 10/2014. you will NOT be able to get that spring back onto that shaft unless you have 4 hands or more. Good luck.
dbld
 
#34 ·
I work at a spring shop, so I always take my guns apart and judge the quality and design of the springs :)

I was pretty surprised when I took my Shield 9 apart. All I've owned is Sigs until now, and I'd never seen the captured guide rod double spring system up close before.

It's an interesting system, where that outer spring compresses about half of the way to full compression before the inner spring begins to do so. Good combination of strength and space savings.

However, it looks like the only way they could make it work was to make the outer spring out of very thin cross section wire. This had the added bonus of being able to use a few closed coils on the end as a kind of retainer, but that method seems to depend on consistently tight and closed end coils for proper functionality.

Making a compression spring with this geometry is pretty difficult, particularly in the cut. I think this is the root cause of most people's problems.

A standard compression spring machine coils the spring out, and usually cuts from the top, like in this video
https://www.youtube.com/watch?v=IjMUlhKGQu0

Imagine cutting against the small edge of the flat wire spring in the Shield. The material is going to want to bend and distort more so than with a round or square wire. Like trying to cut a steak while standing it on its edge. That's a bad analogy but I think you get the idea.

It's my belief that the flat wire spring is shipping with a lot of variance in the end/retainer coil due to the cut. If you get a good one, the coil is tight around the guide rod and doesn't cause problems. If the cut distorted the end coil, there's a possibility of it coming unseated from the guide rod.

If you're feeling adventurous, you could try to carefully flatten just the very the end of the spring and, if necessary, squeeze on the OD of the end gently with pliers to make it smaller. This will make reinstallation more difficult, but if you can get it back on without throwing out the diameter again, it may work.

My spring isn't pretty, but it works and I don't think it will come unseated.
 
#36 ·
There is no snap-ring or any thing on the end of the spring on my SHield. This is sprin g #3 from S&W. They have all been about the same except that the second one came apart.

I've tried writing to everyone who makes springs. No one has a real plan for a Shield version. One of the folks told me that the spring as it comes from S&W was nearly optimized and that there was little that they could see that they could do to help it. That source told me he had a Shield himself and would make a spring if he thought he could improve on the original, but he saw no way to do that.
 

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#37 ·


This is the same Guide rod =- spring assembly from 2 sides. 180 degrees apart. Note that the spring is riding over the tip of the rod in the right picture.
I would think there should have been a washer between the tip of the rod and the spring.

I have two of these assemblies and they are both the same. I have seen pictures on this forum that do not look this bad. :rant:
 
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