What causes magazine spring fatigue? Constant compression from being fully-loaded, or repeated compression/decompression cycling?
Can you pre-load magazines and keep them in extended storage without concern about spring fatigue?
Should you have multiple sets of magazines to cycle ammunition into and out of?
We have the answer, and it might surprise you.
The US Army Armament Research, Development and Engineering Center at Picatinny Arsenal set about finding the answer, and published their findings in Technical Report ARWSE-TR-16035, “Performance of 5.56mm 30 Round Magazines After Extended Loaded Storage,” August 2017.
300 magazines were fully loaded, and for the next 5 years 30 magazines were fired for performance data collection every 6 months.
Spring pressure was measured when the test began, and again at the time the magazines were pulled from storage. Stoppages were counted during the live fire testing.
The data analyzed and published:
NOT A SINGLE MAGAZINE-RELATED STOPPAGE.
The next time you deploy, you can be confident that the pre-loaded magazines sitting in your vehicle bailout bag, or in ammo cans secured in your vehicle are reliable.
And, you certainly won’t have to buy multiple sets of magazines to swap your ammo in and out of, over the course of your deployment, like I used to do.
Just load your magazines, and keep them clean and protected. They’ll be fine.