Storing loaded mags

[Rocket57]

I keep a mag loaded with hollow points for home defense. Periodically I will remove the cartridges and load them in a different mag. I put the empty mag in the gun (XDM9) and it would not lock the slide open when cycling it unless I pushed up on the mag while pulling back the slide. All the mags that were left empty worked fine.

Am I weakening the spring in the mag by leaving it fully loaded for a couple months at a time?

Next range trip I will try it out and see what happens when actually firing it.

 

[acarnahan]

I leave a mag loaded all the time in my glock. My mags are numbered and everyone couple months I'll remove the hollowpoints & put them in the next numbered mag. I've never noticed any "compressed spring" issues in doing it this way.

 

[billybob44]

Mag Storage?

Some mag springs can get weak while storing them full of ammo. On the other hand, some Hi cap. mags are almost impossible to install the last round. On those "Tight" mags., some Mfg. (Glock is one) will recommend that you leave them fully loaded to compress the springs slightly. I have found that to be true on my Glock Hi cap mags.. Bill.

 

[Walt_Jabsco]

This seems to come up on a regular basis. As I understand it, keeping the spring fully compressed or leaving it in a relaxed position makes no difference to wear. The primary wear magazine springs experience is based on constant compression and un-compression, like when loading/unloading or firing.

 

[ThrottleJockey]

This seems to come up on a regular basis. As I understand it, keeping the spring fully compressed or leaving it in a relaxed position makes no difference to wear. The primary wear magazine springs experience is based on constant compression and un-compression, like when loading/unloading or firing.

^^^THIS^^^
it is the full cycle of a compression followed by (an eventual) decompression that wears and weakens a spring. I'm not going to search but there is an explanation from a physicist on here somewhere and google will explain the reason behind it. Storing a mag loaded or unloaded makes no difference.

 

[jajwrigh]

I keep my Glock loaded with a spare magazine loaded as well. Better safe than sorry...

 

[Drail]

People keep saying that leaving a mag spring fully compressed for long periods has no effect. That is only true if the spring is properly tempered and made from high quality spring steel. As a former smith I will tell you right now that not all of them are. Unless you have replaced your mag springs with good ones from Wolff or ISMI then you don't really know what you have. I have seen lots of mag springs fail from storing them compressed (especially in high cap mags where the spring is pushed to the absolute elastic limits of the metal). With good springs and not having it pushed past its design limits (as in a single stack mag) you can certainly leave them loaded. But never assume that all springs are the same. Ask any police armorer who has worked on shotguns left loaded to full capacity locked in a cruiser rack for a long time. They'll tell you that most of those guns would only feed the first round or two and then choke. After replacing the mag springs they were 100% function. The point I am trying to make here is that if somebody tells you it's okay to leave mags loaded and the springs only wear out from compression and expansion they don't have all the facts. Just because they've never seen one fail does not mean they know what they're talking about. There's good springs and cheap springs. If you really need to keep your mags loaded then download them by one or two rounds. Having that mag work when you absolutely need it is FAR more important than how many rounds it contains. Trust me. Spend a little money and buy new quality springs if you're going to leave them loaded or leave them down a couple of rounds.

 

[ATM]

...Periodically I will remove the cartridges and load them in a different mag...

This practice is almost certainly wearing the spring faster than just leaving it loaded.

Another link to the old article:
Magazine spring madness: 'creep' to your 'elastic limit' to un-earth the urban legend of 'spring-set' | American Handgunner | Find Articles

Decide for yourself.

 

[maxmayhem]

well

so when u switch out mags to take pressure off you are actually wearing them out...one would think that the constant downward pressure from a loaded mag would weaken the spring...i guess this is why i work in real estate

This seems to come up on a regular basis. As I understand it, keeping the spring fully compressed or leaving it in a relaxed position makes no difference to wear. The primary wear magazine springs experience is based on constant compression and un-compression, like when loading/unloading or firing.

 

[Jay]

To put this one to rest, you have to understand creep. Creep is the slow flow of a non-ferric metal like copper, brass and lead under force. At temperatures outside of a furnace, steel doesn't have any appreciable creep. Under most conditions, steel flexes and then returns to its original shape. When pushed past its elastic limit, steel will bend and not return to its original shape. All designers of well-made magazines make sure the spring never approaches the elastic limit when the magazine is fully loaded. Honest. This means the spring will not weaken when the magazine is fully loaded -- not even over an extended time. Like 50 years. American Handgunner recently ran a story about a magazine full of .45 ACP that had been sitting since WWII and it ran just fine on the first try. So there you go.

Magazine spring madness: 'creep' to your 'elastic limit' to un-earth the urban legend of 'spring-set' | American Handgunner | Find Articles

 

[rotortech]

Interesting topic and you guys make some good points. The smith says he's seen it a lot. Others say it doesn't happen. I have designed and used springs in a variety of challenging machines. When the spring is being pushed to fairly high stresses you get creep. Also, as mentioned above, manufacturing variables can affect how the spring "ages". So the properly designed and manufactured spring will last indefinitely in full compression. The question becomes - Is your mag spring properly designed and made? I think the vast majority of them probably are.

I keep magazines for my guns loaded. You know, in case I need it quickly.

 

[kwatters]

I keep ALL my mags loaded, never had a problem. Besides, how much good are they if you need them and they are empty?

 

[Jay]

I keep ALL my mags loaded, never had a problem. Besides, how much good are they if you need them and they are empty?

Gee whiz... you mean the intruder won't wait until you get yer mags loaded?