Oldvet50 asks:
How long can you safely store a loaded mag before the spring weakens and causes misfires?
The answer to that depends on the magazine manufacturer. Cheaper magazine manufacturers, especially ones with polymer feed lips, are more prone to failure. Not of the spring, but of the magazine itself. Scorpion had a well documented issue with that. It turns out that the factory Scorpion magazines would dry out when left in a dehumidified safe for long periods. That’s why the Scorpion PMAG is a better choice than the factory one.
With a quality magazine, the answer to that is decades. Magpul themselves claim that they have had magazines fully loaded for eight years, and they still function.
The damage is done by compression and decompression of the spring. The more cycles that a spring goes through, the more it weakens it. I wouldn’t worry, however. It takes thousands of cycles to wear out a spring. Still, I think of magazines as consumable items, which is why I have so many of them.
SmileyFtW asks:
Why the waste of space with the foam? Load the cans tight for maximum capacity I would think. Same stuff in one can; label the can and move on. If one can is to be an assortment, say so on the can and ID the contents so it is obvious to what each one is
That was actually what I was doing up until now. What I got was cans that either contained a bunch of different mags in the same can, or the can wasn’t full. Example. Let’s say that I have a bunch of Smith and Wesson magazines:
- 12 magazines for a Shield 9mm
- 8 magazines for a Shield 40S&W
- 6 magazines for a Shield Plus
- 30 magazines for an M&P9 9mm
- 12 magazines for an M&P9C 9mm compact
- 12 Magazines for an M&P40 .40S&W
That’s 80 magazines. They will likely fit into one caliber can, but they aren’t cross compatible. The worst part is that some will fit in the handgun, but not function. For example, an M&P9 magazine will fit in the M&P40, but you don’t want to attempt to fire it like that. So with this system, good luck finding the right magazine in a hurry.
Another reason for padding them is preventing damage. One of the biggest reasons for malfunctions in a quality handgun (that isn’t a 1911) is a damaged magazine. My carry guns are life saving equipment, as far as I am concerned. The number one quality that I need in a carry gun is reliability. I need to know that it will go ‘bang’ every time I squeeze the trigger. Since quality handgun magazines cost anywhere from $35 to $60 each, having 100 magazines is a significant investment. By padding my magazines, I am protecting them and my investment. I lower the chances of malfunction which will, at best cost me some range time and money replacing it, and at worst will cause a malfunction during a firefight.
That’s also why I number my magazines. I know which ones have malfunctions. Note that number 2 and 5 are both missing in this picture. It’s because they are currently loaded and ‘in use’ by one of my handguns.

It’s a simple numbering system. If it starts with a 9, it’s a magazine that will fit the S&W9. If it ends in a “c” it’s for the M&P9C. This makes sense in my mind, because the compact can accept the full sized mags (but not vice-versa). The magazine numbers that start with a ‘G’ are for the Glock 19. (That’s the only model of Glock that I have, thanks to Project Gaston)
A similar code works, with the M&PShield Plus mag numbers all starting with ‘P’, the 45 magazines starting with ’45’, etc. I have a spreadsheet* that I use to track magazines, ammo, firearms, and firearm spare parts.
*I also keep a list of spare parts on hand: springs, firing pins, sights, and other fiddly bits. That’s why I have so many M&Ps: common spares, and the best spare part is simply having a spare pistol. Not only that, but I also know how to detail strip and troubleshoot the M&P series very well, which simplifies repairs. The Glock is easy to do the same with, but I generally don’t like the way that the Glock fits my hand. I’m still learning all of the ins and outs of the AR system.
