yeah fixed that above. I'm a huge fan of Pmags for the AR platform - gen 2 Pmags specifically. With my Gen3 Pmags, I've got three that won't seat when loaded with action closed. I don't have a Glock, so can't speak to their pistol mags.

Glock PMAG 15 and 17s work fine in my experience. Although I dislike the fat basepads on the 15s, so they are range only for me (OEM for carry).

I keep a bunch of AR15, Glock, FN SCAR and HK pistol magazines loaded. For months and years.

Zero issues with form or function of any of them.

quote:

Originally posted by Art in Colorado:
I read years ago in a magazine that the author knew a W-W II vet who died and he went to help the widow out. He found a loaded 1911 from that era in a bedside end table that he thought was left loaded for several decades. He took that 1911 without any maintenance and shot till empty without any problems. So with the mag springs that we have today is it a problem to leave them loaded for pro-longed periods?

I had posted about this a few years back. I recall it well.

When I retired as a LEO in 1997 I was given my Sig P226 and several magazines - over the years somehow one magazine was misplaced, fully loaded with Winchester 147 gr. SXT's. I found it 18 years later.
Rather than manually unload, I put it in the P226 and fired at the range. It functioned with no problems.

Don't think you have anything to worry about as long as it wasn't left out in the elements.

I think "standard capacity" mags last just about forever, but a lot of modern mags are designed specifically to fit more rounds into less space, and spring strength/life suffer.
I had some factory 14rd mags fitted with basepads that allowed them to hold 18 rounds if a coil were cut from the spring, and I wouldn't trust those to work for more than a year.
I kept a mag loaded for over twenty years, specifically as a test, and the three or five times I took it out for a test, it worked perfectly.