Hey guys, it just dawned on me the other day that i've had about 10 mags with 30rds stored in them for about a year now.  Is this bad?  They are USGI mags, original issue, black follower, etc.. so is this going to cause issues requiring new springs?

I also keep my Glock mags loaded (its a .40 so i keep all 10 loaded)... i ask because some places say its the load/unload that wears the springs and some say that loaded mags lead to weak springs.

help!

Properly designed springs wear out through compression/decompression cycles, not from remaining compressed over time. USGI and Glock mags contain properly designed springs.

Thank you so much!

My concern is not with spring life but with the life of the mag body.  It seems that all that force could bulge the mag body over time.  I have bought old GI mags that are loose and springy at their mouth.  Sometimes these mgs will let two rounds pop out into the action and cause very bad jams.  I do not know that this comes from storing them loaded; it may just be from alot of usage.  Does anybody know if storing mags loaded can cause the mag body to bulge?

This had never occurred to me! Oh boy... anyone have any ideas?

I have several mags I rotate through the loaded/unloaded cycle when I remember to do so.

MM419

Howdy DJ and everybody else.  Just for everybody's information, I just used up 9 30 round mags about 2 months ago. These had been stored in the back of the closet loaded with 30 rounds of WCC 1985 M193, since 1988 (I always put a note in the cans showing date of storage, and when loaded - if they're reloads).  These were/are all USGI mags, stored in GI cans with dessicant packs.  I don't usually have 'em around more than a few weeks, but I'd stashed these in '88, and just plain forgot about 'em - kinda makes me wonder what else I've stashed and forgotten :-O  BTW, they all functioned 100% flawlessly - no FTF, or anything else.  No problems with the ammo, either.
HTH,
Mike.

FYI:

Just shot my way through 6-30rd mags (loaded with 25rds each), and also 3-20rds (full) this morn.I was trying out a new upper, and Trij Reflex . The mags had been stored since 1995 almost eight years to the day, and I had no problems at all.

I found em in what I thought was a can,with bandoliers, that had been stored since I moved. Whoohoo like finding money in your coat pocket!

Normally I 'rotate' mags (shoot out) about once a year if not sooner. However I only load 25 rds in 30rd mags (old habits die hard, and I would rather reload, than clear a bolt over, even if I am plinking). Never have had any problems with this system in 15 years.

For all practical purposes I think good 30rd or 20rd USGI mags  can stay loaded till you need them.

I test all mags as soon as I can after I get em, if they consistently fail I mark em and give em to someone I dont like (jk).  

I have no idea how long term storage works in thermamelts, ramlines, MWG 90 rounders or other 'plastic' magazines.

I have seen some thermolds (sp?) with very strange looking bulges. And MWGs that have very loose lips. But I do not know if those are storage, or heat/use/abuse issues

The Chinese drums are supposed to allow indefinte storage.
                         HoG

Guys... relax.

With the change in temperature, even in a closet, all metal expands and contracts.  Even empty mags are subject to the effect of temperature.  Loaded mags have a slight advantage since the compressed metal spring is less able to expand.

They will all wear out eventually.  However, unloaded mags are like empty gas tanks.  What good are they to you if they are unloaded?

TRG

Thats why i keep them loaded...

I use some Thermolds as well, i have a pair thats doubled up in the rifle at all times (who knows when i'll need a quick 60 rounds?)

Anyhow, those i cycle a lot, but the USGI's are the workhorses when it comes to a real need :)