Leaving Magazines Loaded

Discussion in 'Valuable Info' started by jonathon, Sep 10, 2005.

  1. Exactly.
    I've considered making one of these. It wouldn't be terribly difficult to make a setup to test a specific spring, you just need a setup that allows you to compress the spring to varying degrees and a second setup that allows you to load the spring with a specified weight and measure the compression that results.

    A test would be to load the spring with Y pounds and measure the compression that results as a percent of the new, uncompressed spring length. Then compress the spring to X percent of its new, uncompressed length for a period of Z days. Then decompress the spring, load the spring with Y pounds again and measure the compression again. Repeat with different levels of compression and varying amounts of time.

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  2. I have considered such a device too, but I don't know how useful it would actually be. The spring testing machines I have seen (pictures only) are dynamic and computer controlled. The computer control doesn't scare me or the sensors...calibration and filter algorithms is what I'm worried about. There almost certainly is a Kalman filter in such a test device, but that has certain linear and Gaussian error assumptions. There are such things as extended Kalman filters that are nonlinear (as well as other sorts).

    If you've ever done navigation systems or sensors o(I have...tactical 6DOF and robotics) stuff the math isn't a problem. It is simply that I know just how much work is required to build a really good machine and to be honest I don't think it is worth it. For the cost and time it would probably be best make a friend and rent some time on one. Don't forget that to get a good sample space you would need at least several hundred dollars of mags (possibly thousands depending on how tight you wanted your confidence interval).

    The issue is not springs, but rather the complex interaction of the system (intended usage, shooter, etc.), the handgun sub-system (in this case a Glock), the mag element and finally the spring (element component). Design, materials, usage patterns, manufacturing tolerances, etc. all matter. Given a proper design (with system requirements that are valid for a duty or self-defense gun...ie reliability matters more then adding one more round, etc.), good materials, sufficiently tight manufacturing tolerances, keeping your mags full will have no impact on mag/spring performance. That is physics. However, I am also certain that to sell guns, some manufacturers have designed mags that do deform springs (static or dynamic properties), used poor materials or quality control, etc. and keeping your mags full or even close too it will surely cause reliability problems. It is your call if you think Glock or anyone else did this or not.

    In fact I would be very surprised if every major, self-defense/duty/military manufacturer hadn't done this sort of test. Governments usually require this type of test (I know this from first hand experience). Also, there is a question of liability (I'm an engineer, not a lawyer so this is just my opinion). If you were to demonstrate (do the tests we been discussing and generate confidence intervals) that the standard mags from a particular manufacturer were faulty (design, materials, tolerances, etc.) with the advertised usage patterns (military/duty/SD usage patterns are loaded mags for obvious reasons), are they not legally and financially accountable for this? I'm looking at you Beretta and your POS M9 that our soldiers are only loading 10rnds due to this very problem.

    At the end of the day it is your life, so do the research/tests and make a decision. IMHO, I'm not sure why you would carry a pistol (and trust your life to it) from a manufacturer whom you think makes a faulty product that can not be used as advertised.

  3. It would be very useful if you were testing to see how much compression is required to permanently weaken a spring. If you were trying to test the complex interaction between all the parts in the system then it wouldn't be very useful at all.
    It is my understanding that the offending mags are NOT Beretta magazines but rather aftermarket mags supplied by a low bidder.
    I don't think that one could call a magazine design faulty because it caused shortened spring life unless the spring life was unreasonably short. Springs are inexpensive and are usually considered to be normal wear parts/"consumables". If it wouldn't even last through a normal shooting session or three, that would be one thing and there would certainly be grounds for calling those magazines faulty. If we're talking about mags that weaken after being left loaded for many months that's another story entirely.

    Furthermore, unless there was a specification for "fully loaded spring life" or a test that verified that the mag design didn't overstress the spring, then there would be little grounds for any action against the manufacturer as long as they could prove that what they supplied in the buy was not the same quality as what they submitted for testing.

    e.g. if I submitted a gun for testing and there was no specification for accuracy and they didn't test for accuracy then they would have little recourse for legal action against me after acceptance if they found the accuracy was dismal.
    #123 JohnKSa, Jan 12, 2009
    Last edited: Jan 12, 2009
  4. Possibly. Don't forget that the very act of loading/unloading that mag would have weakened it. Unless the results were large or you tested a large number of mags, I wouldn't consider it conclusive.

    Perhaps something could be built that used the standard Glock loader and new mags. I have four new G32 and two new G19 mags (never loaded as far as my knowledge). First I'd have to test the force required to compress the mag enough to allow the loading of one round. Then two rounds, etc. until full. If the resulting curves are close, then the device might be useful. However, with such a small sample space it hardly would be conclusive. Interesting, but not conclusive.

    Then I would need to unload one G19 and two G32 mags, while leaving the other alone. Now how long is enough to test this? Perhaps after one week unload the mags that were left loaded and then repeat the test for several weeks? As long as the origional curves were similar and the number of cycles were kept the same, the only difference would be how long they were compressed.

    Give me some time to consider this. I would only be measuring the static load at various intervals, any sort of dynamic interaction would not be measured.

    That is what we have been discussing. If I provided mags for the M9 for soldiers, there is reasonable expectation that they should be able to load mags to the max and leave them there for extended periods. To suggest anything else is sort of absurd. I would argue that the police/FBI/SS/etc. and self defense have similar requirements and usage patterns for mags.
  5. G2145

    Wife bought me a BDA .380 for service backup about 1977 or so. A sweet little piece. It has (4) 13-rnd mags that have been full since the day it came home and they still feed flawlessly. A half-dozen 30-rnd AR's have been full for several years and they still feed without a problem. ;-)
  6. I would be more worried about the rounds than the spring in the mag also. My brother unloads his expensive wolf ammo to go shooting with cheap fiocchi every weekend and reloads the same 14 wolf rounds in his P99 mag every week. I would shoot them off and replace them personally, but he insists that they are fine.

    I believe that rounds that stay in a mag are fine over a long period of time, but not if you are loading and unloading the same ones constantly.

    I've got two mags of hornady that i'm keepin around, but I also have two other mags to take to the range. I'll probably cycle them through every couple months and replace them, but without carrying, I don't think any wear or damage will result of it.

    Mag springs are cheap anyway. My followers show wear before my springs do.
    #126 jimustanguitar, Feb 3, 2009
    Last edited: Feb 3, 2009
  7. Glockdude1

    Glockdude1 Federal Member

    Expensive Wolf???

    Wolf as carry ammo???

  8. I know... I'm a hornady fan, but he bought a box that was about $80 for 20 rounds or something ridiculous like that. don't ask me... I guess not being a respected brand is all the more reason to shoot 'em off and load something new in the mag.

    I've only had one misfire out of over a thousand rounds in the last couple months. It happened to be the first and only fiocchi box I'd bought. Winchester is usually what I take to the range because it's been reliable for me so far. Not one missed round.
  9. randyinaloha

    randyinaloha Old Guy

    I thought Wolf was "Cheap" ammo...

    Anyway, with all the talk here about spring wearing out with use I guess I need to make a spring pushing machine to weaken mine.
    I just cannot get the 10th round in without a hammer and I am very hesitant to do that. I did see my boss hammering his expanded reloaded .45 Long Colts into his revolver and I stood back and out of the way. Kinda scared me, but what do I know...
  10. erichodges

    erichodges Senior Member

    you'l wear out b4 your glock mags do
  11. erichodges

    erichodges Senior Member


    RANGER 9mm +p BONDED JHP 124gr. :supergrin:
  12. "Don't forget that the very act of loading/unloading that mag would have weakened it."

    But that's what happens when you shoot up the magazine and reload it and shoot it again and....you get the idea.

    "You'll wear out b4 your glock mags do."

    Hopefully not. You can buy rebuild kits for Glock magazines. New springs in an old magazine makes it work like new. Unfortunately there's no rebuild kit for me.
  13. Glockdude1

    Glockdude1 Federal Member

  14. mossy500camo

    mossy500camo ammo found

    All of my mags stay loaded.
  15. Glockdude1

    Glockdude1 Federal Member


    Only now, my magazines will stay loaded longer. With ammo prices the way they currently are, I won't buy any more ammo, until the prices come back down. (fingers crossed)

  16. Been lurking for a while so I thought I better register in case I wanted to post.

    This mag issue probably has a thread on every gun forum out there. Who knows for sure which is the right way but I'll keep rotating my carry mags every month or two just in case.
  17. Just a question...if you loaded them three years ago...how do you know if it still fires? wouldn't you still have the same three year old ammo in them?
  18. Glockdude1

    Glockdude1 Federal Member

    The mags will work perfectly. Ammo will last forever if kept cool and dry.

  19. Great info and I totally agree on the elastic limit theory!
  20. What a great thread!!!!

    leaving mags loaded and weak springs are a very extended myth around the world.

    (like a Mythbuster challenger)

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