I’ve always preferred USGI aluminum magazines for my AR-15 over plastic mags. I like how the aluminum magazines lay flat against each other, the way they lock into the rifle, and just about everything else about them.
Last night I did, however, find their weakness. Every month of so, I shoot an action rifle match at the Wake County Firearms Education and Training Center. These action matches require reloading on the move, and while executing a reload last night, I let a partially full magazine fall onto the concrete floor (as I usually do), and this magazine suffered dearly for it.
You can see below that the feed lips are no longer square, the bottom feed lip has a large dent at the right of the picture, which has knocked the entire feed lip out of line.
The magazine happened to hit the concrete at just the right spot at the rear of the feed lip, right near the rim of the top round, and the impact actually formed part of the feed lip around the case rim. I’ve never had this happen when dropping magazines on dirt or gravel, but apparently concrete + a mostly full magazine was too much for this magazine.
Now I’m sure someone will come along and tell me that this isn’t a big deal, and that the magazine will probably function just fine. Well, I thought of that so I tested it, and what I found was that the magazine will still feed dummy rounds into the chamber without issue, but every now and then a round will feed just right into the notch, and it will actually hold the bolt right there. (Excuse my filthy rifle, I’m out of Brakleen, so it hasn’t been cleaned in a while)
I think I’ll start using PMAGs when shooting these indoor matches from now on, as they tend to bounce a little more when impacting the concrete instead of cracking or denting.
Magazines are wear items, and they break from time to time. It sucks that I have to buy a replacement, but it happens. When taking training classes, or shooting competitively magazines get thrown, stepped one, filled with mud, etc. It happens. I have a couple magazines that are dedicated for self defense use, and other magazines that get beat up on the range. It’s important to check your gear from time to time!