My dad passed away 3 years ago and I'm still going through his gun stuff.

While doing this today I found an ammo can with loaded mags.   It looks like these we're his "ready" mags.

These were loaded before Sandy Hook as I remember him making a comment then along the lines of being glad he had his mags loaded up a few years back.

USGI Mags - these we're fine and still ready to go.

AR Stoner mags. One was coming apart at the spine. This was all the way down, not just at the feed lips. The other seemed fine functionally, but was turning bright purple from the top down. I have seen this on a few other of these mags. One un-modified mag he had was entirely purple.

Lancer. These were the early version. Not the L5 version we see now. These only had a small steel insert. Both seemed fine.  They would lick into the first 4 lowers I tried. I did unload them as they were the old style though. Not sure how they stack up long term.

Troy Battle mags. There were four of these. They were unusable. I could get them into SP Colt lowers with minor drag but Colt SP2 Colt lowers we're difficult. Nothing else was even close.
I unloaded these and trashed them. Feedlip spread was visible from the moment I picked them up.
I always considered these reliable but disposable. This reaffirmed this idea for me.

The lone Orlite was cracked and held together by a metal mesh of some sort. I junked it. Not worth looking into any further.

PMags. Mostly M2 with a few early models in there as well. All had the covers on them though a couple had popped off over time and transport.

Of the 7 I tried, all were good to go. There were over a dozen more but I didn't check. I figured they were fine.

Side note, all mags were loaded to 28 rounds. I topped off the good mags from the bad ones and put them back into the "ready" box.

Not scientific I or all that unexpected I know, but I thought I would share.

I've got some USGI's that have been loaded since 2005. Some day I'll pull them out and check them. I think I've got about 100 of them in one tool box.

I have GI mags from late 80's early 90's and they've been loaded 50% of that time.  I load 30 at a time, use up 6 or so at a time, then when all empty load 'em all up again.

Zero issue

I've got Glock mags that have been continuously loaded since 1996 when I bought my 26. Never a problem.
Cycling the springs is what wears them out.

While cycling is what wears them out in properly designed magazines, not all firearms have properly designed mags.

Thankfully glocks and most ar mags are properly designed.

My M2 Pmags have been flawless

Curious about the "purple" issue.

What caused the discoloration?  Mold?  Were they stored in a wet / humid environment?

Did the discoloration affect their functionality?

Every single AR magazine I leave loaded for long term storage is a quality GI. All with 193 and 855. Simple and a known quantity.

I have a shitload of other ammo and mags as well but loaded I prefer them GI.

This one was in an ammo can with desiccant inside.

I have had some do the same or have the entire mag go purple under both optimal conditions and while in the garage. No rhyme or reason.

It almost looks like an under coating....like some old USGI mags would turn gold. That sort of thing.
I have noticed this only with a handful of mags. All in the black finish. All AR Stoner floor plates.
This far out many of them are starting to fail at the weld on the spine, but I really don't think the discoloration has anything to do with it.

I started noticing this on a few of my mags about 3-4 years ago. It is almost an irridium purple.  Not a bad color, just not on my black mags.

Thank you for posting this

I've had 5 pmag mags loaded to capacity since June '08.  I'll post next year when I pop the dust covers and let brass fly.  I think they'll function 100%.

purple = black anodizing fading.

purple fading from black means the black dye was primarily made of organic matter
brown fading from black means the black dye was primarily made of ferric matter or oxides

most anodizing dyes use organic matter to achieve their tints. organic matter breaks down over time and thats likely what you are seeing. if it has a slightly tacky feel too it or when you handle them and you can see the oils from your skin attach to it thats a sign of bad sealing at the end of the anodizing process.

fading from poor sealing or lack of nickel acetate sealing is usually a sign of it breaking down from heat exposure or corrosive humid air.

Interesting, thanks for the info.

A couple of mine that were left in the garage were completely purple.

Funny thing is, only the AR Stoner mags did that.
I think that says something...but I think it has been said many times before.

Interesting information.  

The only one I've ever seen fade to purpl-ish, was a couple of C-Products mags.  I think they were the stainless steel ones that had some sort of black finish on them when I bought them.

C Products and AR Stoner are the same I believe.

I've got GI M14 magazines that have been loaded for almost 40 years.  They've gotten "unloaded" at the range but get loaded up again when I get home, and then sit loaded till the next range trip.

I've got AR magazines that have been loaded/unloaded the same way for 10 years now.  These are all GI style (aluminum magazines).  I do have some PMags, but they are newer.

I've got 1911 magazines that have been treated the same way for 40 years now.  

No issues with any of these.

Good magazines are good magazines.

I have a friend who did a 25 year test with used GI mags. He loaded 25 used mags and shot 1 mag a year. They have almost all been solid and reliable. They were all used when he loaded them. I was with him for the 20 year magazine.

Thank you for the post.  

Long-term storage experience is rare and that makes it valuable.  

I have had no problems with my P-Mags, but since they are polymer and plastics subjected to a continuous load will experience a change in dimension known as "creep", I do not keep them loaded.  

In fact, I keep most of my magazines unloaded to reduce unnecessary wear on them.  

I do keep a few magazines loaded so as to be "ready to go", but they are blackened stainless steel magazines from C-Products which I feel are most likely to not be adversely impacted by being left loaded.

I'm on year 18 of a 25 year storage test of the Thermold"30/45" "storage" magazines.

They aren't made any more, but they were guaranteed to last 25 years continuously loaded.

If not, I'm demanding a refund.

I found 5 loaded Ruger Mk II magazines.  Based on who owned 'em, etc. they had been loaded for 15 years.   All 50 round fired and cycled just fine, and I'm still using the mags 15 years later.

For 5.56 it keeps coming back to real GIs, Magpuls and Lancers.

Why is Glock on their 6th redesign for mags then?  

I have a theory that Glock probably has some of the most problems by any gun manufacturer but people don't report the problems like they will other companies.

Glock has said they tinker with the followers to optimize for the latest trends/styles of hollow points. The bodies just go thru evolutionary changes to take advantages of newer poly formulas.

Iv got 9mm mags that have been loaded close to 30 years. Only reason I unloaded them was to replace the pps ammo with gold dots.

If you think of a mag spring, when it's loaded its only moving 1 end of the wire like 3"  from the other end.

If you pulled that spring out and pulled it straight, it would move 3 inches just picking up the wire....

Zero issue.

There are literally millions of 50 year old cars out there running around on the oem springs.