Magazine Study

[DadSmith]

I have a bunch of cheap polymer SWT mags from Sportsman's Guide that have been loaded and forgotten about for eight years (bought, loaded, and stashed them away in March 2015). I just found them at the bottom of a bin while reorganizing my gun room. Threw a few in a range bag and they functioned without problem. No cracks or any other issues with the lips.

Not gen1 PMAGs I realize, but eight year old rando plastic nonetheless.

I bet 8 year old promags wouldn't work. Pretty much like factory fresh promags

 

[Tactically Fat]

Isn't materials engineering neat?

100% polymer mags can swell. It happens.

Random area of metal fatigue on rifle or pistol mag? It can happen.

Mag gets dropped and lands a certain way with a certain amount of force and cracks a weld that weakens and worsens over time until it fails spectacularly? It happens.

Bad heat treat on a spring? It happens.

The real lesson we should take to heart is that no matter the platform, magazines are a consumable part. Magazine components are consumable parts. Because things happen.

Related: a few years old now (maybe even 4-5?): I listened to a podcast not too long ago that featured some custom 1911 / 2011 builders. One of them was Joe Chambers. This guy: https://chamberscustom.com/about-us/

He/they test fire every gun a minimum of 100 rounds before they ship. He said that his test mag for all his single stack guns has well over 100k round through it. And is/was still working just fine (at the time the podcast was recorded).

 

[slibhin]

Pretty sure I read about a US army storage depot that found mags loaded since Vietnam and they still functioned.