everything I read and hear says staying compressed doesn't hurt spring steel, it's the compression and relaxation of the spring that wears them out.
You can only have so many magazines, but I'm glad to see prices coming back down for PMags. I also wonder about the effects on the springs of being loaded for long periods of time.
This is current internet wisdom, but I disagree with it.
I have two brand new / never used Glock mags that I stored with one less round than full capacity for a couple of years, and the springs have noticeably less resistance now when compared to two mags I bought at the same time but stored unloaded.
Use does wear out a spring, but compression also causes the spring to "take a set" or weaken.
