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Discussion Starter #1
I've shot over 1200 rounds with my SEI M14 and it shoots great thus far, but how long should I expect the springs to be serviceable? I've read Gus Fisher's report recommending changing the Op rod guide spring after a 1000 rounds on match rifles; but what about a combat rifle? What is the service life of USGI springs vs commercial springs---or are they the same? I have a set of Tubb's CS springs for operating guide rod and hammer, but have not installed them yet. Any reports on these either negative or positive. It says they last 100 times longer than the standard spring, lasts 500,000 cycles, delayed bolt unlocking, improved feeding, longer parts life--ect? I guess my concern is how this chrome silicon material would perform in extreme cold, like 30 below. I've rangered for US Fish & Wildlife Service in Alaska before and may end up there again someday. I just want to get it right.

Thanks to anyone who can tackle this.
 

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It'd be up to you. You know what you have is good for spares if the Tubbs aren't to your satisfaction. If the rifle works better with the new springs then you'll know it needed 'em. Let us know.
 

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Extreme cold... not much of that in So Cal, but the Tubb springs run great in my setup. Can't see where cold would be an issue but like I said, we don't get much of that here. I say swap them out, I have yet to read about anyone having issues caused by Tubb springs in their M14 platform.
 

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I don't know about really cold weather but I've been using the Tubbs springs in weather that has been as low as -10 and they seem to work well for me. I've probably only fired a few hundred rounds total in that kind of weather and most of my cold weather shooting is in the mid to low 30s right now but I've had no problems with the Tubbs springs.

As for replacing the springs, well my first M1A was a standard model that I bought in 1980 and I didn't change the springs until last year. I have no idea how many rounds I've put through that rifle but I'd say it was well over 8,000 rounds and it was still functioning reliably. During most of that time my shooting style was more closely related to combat style shooting so I don't know how the springs would have affected a more formal and precise shooting style.
 

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I see a lot of op rod springs that in the range of between 500-2000 rounds fired, and invariably, every one of them are 14 1/2" instead of 15 1/2".....I would say shoot em till they are 14" and replace or when you have a problem, if not on a match rifle........I hate losing, especially for a malfunction.......spares are a good thing and can be lashed to your pack with little or no weight increase or room taken up.

I don't pretend to be an expert on chrome silicon or anything for that matter, but in my opinion, I believe the chrome itself would lend itself to being more brittle than regular steel, I don't know, just stuff I've read, perhaps one of our mettalurgy experts will chime in.

I'm not sure about Tubb's, but find it hard, after what I have seen, to expect 500,000 cycles out of any spring in the M14 without a remarkable collapse of length. We should all be so lucky as to live long enough to accomplish this test....and rich enough.....heh heh.....
 

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every one of them are 14 1/2" instead of 15 1/2"...
+1
Once I learned about the incredible shrinking spring phenomena I checked mine and that's why it replaced it last year. I knew springs would shrink from usage but man I had no idea how much!!
 

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Discussion Starter #7
Thank you for that---

I measured the Tubb spring and it came out to 15 1/2", so that's good. I suspect also the chrome could get brittle in extreme cold, I guess lower than -10 according to Ramm's experience, so that gives me a good baseline.

I've read somewhere that Marines use carbon barrels and not stainless steel in arctic environments, maybe for this same "brittle" reason. In fact that's what spurred the question regarding the chrome silicon springs. "Silicon" makes me think of flexibility however. Just groping in the dark here. Metallergy is not my strong area by a long shot.
 

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+1
Once I learned about the incredible shrinking spring phenomena I checked mine and that's why it replaced it last year. I knew springs would shrink from usage but man I had no idea how much!!
While I am no metalurgist, I do know that the op rod spring length is very important. The spring strength/length affects the bolt recoil velocity. The rear of the bolt impacts the rear of the receiver, and more velocity means more impact force and can in time cause the rear receiver heel to crack. You can then kiss that receiver "good bye".

Higher port pressures from too slow burning powders to very hot loads can also have the same adverse effect.

The service life of the Tubbs springs are much greater that the original USGI springs, and I highly recommend them. Pretty much install them and forget about them.

I've heard of M1 receivers cracking from firing blanks with a dirty, plugged up blank adapter, and the much higher port pressure caused the bolt to recoil with such speed to break the receiver.
 

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Recoil Springs

I shot my match M14 until the op rod spring failed.

Here is what happened:
The spring lost tension against the spring guide. Under recoil the lack of spring tension allowed the guide to move forward releasing the front magazine catch. The magazine dropped down in front causing the next round to misfeed. The tip of the bullet jammed against the bottom of the breach face. At this point, the overall free length of the recoil spring was about 14.25".

This is not too serious under normal conditions, but a real pain in the middle of a rifle match. Keep in mind that the spring worked fine up to that point. It would have been better to change the spring before this situation occured so Gus made a good point. 1000 round spring changes may be a bit premature, but it would prevent problems like I experienced.
 

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IMHO, USGI springs when new are as good as anybody's. Now, in real cold weather - zero F and below - there will be peculiar challenges regardless. The rifle greases we use in normal temps aren't that good in the deep cold. A Garand will still run below zero so I guess a 14 will, too, though I've never had occasion to test it. I think I'd wanna lube on the drier side, though, like graphite or messy moly. This irrespective of the springs. Any gun exposed to real cold temps for long is going to have some functioning hiccups.
 

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Discussion Starter #11
So basically what I'll take out of this is to measure my spring when I clean the rifle and when it gets down to 14 1/2", replace it with the Tubbs until I hit really cold weather. Then have a few carbon springs in my pack if needed. Sounds like a plan!

Thanks guys
 

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Discussion Starter #13
Well thank you for that--it looks like the Tubbs springs are the real deal then. I didn't know it got up to 500 degrees under the handguard when ripping off some rounds. The USGI 17-7 cold drawn stainless recoil spring rated for 600 degrees, and the Tubbs 700 degrees. It's nice to know these springs are as good as advertised. Just put the Tubbs in and forget about them.
 

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Lube it!

In extreme cold I would worry about proper lubrication first. A lot of cleaners/lubricants have more water in them than one would expect which can cause seizing and troublesome operation. The TM should have a lube order for extreme temperatures.

GI6ARMY1AIRASLT
 

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Just install the Tubb for the Op Rod, don't worry about the rest. Buy spares for the future.
 

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That clears it up for Op-Rod springs, but how often does everone change their other springs? (i.e hammer springs, etc etc.)
 

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I've got somewhere past 5,000 rounds on my M1A and I just noticed the operating rod is leaving some "kiss" marks on the front lower receiver. Never noticed it before but its there now.

I think I'll order a couple of springs tonight.
 
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