A self-loading pistol without a magazine is at best an awkward single-shot firearm. And some aren't even single-shots. If your pistol has a magazine disconnector in it, without a magazine you have an awkward club. So it behooves you to buy good-quality magazines, treat them right and keep track of them.

Let's start with new mags. The old adage "If it seems too good to be true, it is" applies in spades with magazines. If they normally cost (fill in the blank) and someone is offering them to you for less than half that, be suspicious.

Once you've bought some, you want to make sure they work properly. First, take each apart one at a time. Look at the follower for chips, dings, tool marks or gouges. You need to smooth out any such imperfections you find.

Check the spring. Is it clean and of the proper length? (If it isn't do not stretch it.) It helps to have a properly functioning magazine of the same brand when doing these inspections. Was the spring in properly? If not, make sure it is when you reassemble.

Blemishes such as the polymer delaminating from this magazine don’t interfere with function, so don’t worry about them.

Put it back together and dry-check it. Does it insert smoothly and drop free of its own weight when you press the mag button? Does it lock the slide open? Does the baseplate stay on in normal handling and function? A "no" answer at any point is a bad sign.

Load it up. Does it hold as many rounds as it is supposed to? Do the cartridges strip off easily with thumb pressure?

Once your magazines pass those inspections, we get on to the only one that really counts: test-firing. Pistol magazines, if they are prone to malfunctions, will usually fail in the first two or three rounds or the last two or three rounds.

Got bad mags? Dispose of them or mark them, but don’t let them get mixed in with your good magazines.

Load your magazines with three rounds and test-fire them. Do this for 10 checks or so per magazine. (Yes, this can get expensive in ammo, but you want reliable magazines, right?) Once they all pass, load them fully and then fire only the top two or three.

Once they've all passed, strip the cartridges out until there are two or three rounds left, and then fire them as limp-wristed as possible. The magazines must feed and lock open regardless of how lightly you hold the pistol. Once they pass all the tests, you can introduce them to the rest of the magazines in your inventory.