No matter how much money you spend on an AR, the fact is that if you want it to run reliably you must use quality magazines. Now this would seem common sense, but more often than not I have run across shooters using either old, worn out or cheap quality magazines.
It can be very frustrating to watch a shooter fight through clearing a double feed, only to re-insert the same magazine, potentially setting themselves up for another double feed. (Not the ideal technique if you are in the middle of a gun fight.)
Rifle magazines are one of those items where every shooter seems to have their favorites. This just makes sense—once you have had a good experience with an item and it works well, why not swear by it.
Getting surplus mags for $5.00 each saves
you nothing if you end up having to turn around and
buy other mags later on because they do not run.
Rather than trying to go over what I think are the best magazines—and since there already exist virtually dozens of shooter reviews both in print and online—just about every magazine currently being offered has been covered. I would like to cover just what you should be looking for in a quality AR magazine.
Knowing what right looks like can save you money. Getting surplus mags for $5.00 each saves you nothing if you end up having to turn around and buy other mags later on because they do not run. (Buy cheap, buy twice.)
By using quality magazines to begin, if you do have feeding issues with your rifle, being able to discount the magazine can save time and effort trouble shooting trying to determine if it’s a loading or chambering issue.
WHAT TO LOOK FOR
Many think that the most important item on a magazine is the follower. While having a smooth, good working anti-tilt follower is a key item, it’s not the only piece that is required for a well-functioning magazine.
The body and overall construction of the magazine itself is just as important. Everything from the feed lips design to even what the magazine is made of plays a part in the overall reliability.
So what should you be looking at to see if you have a well-built magazine? Whether you use aluminum or polymer bodied mags the areas you need to look at are the same for every magazine. Depending on what the magazine is made out of will determine what you are specifically looking for in those areas.
For metal magazines (aluminum or steel) usually the body of the magazine itself consists of two pieces of metal joined at the front and back (both pieces overlapped and pressed together.) How the metal is joined at the front of the magazine (bullet tip side) is joined is the area you need to look at.
If not done correctly you can have issues with the rounds being able to feed up while inside the magazine as the nose of the rounds can drag on the inside of the front wall.
Looking straight down at a metal magazine the two pieces that join and overlap on the front of the magazine should be even against each other. If the two pieces are unevenly pressed together what can happen is the inside flap of metal can protrude into the magazine itself. (This is basically a sloppy construction job.) If the tips of the rounds are touching this metal fold they can drag on it on the inside of the magazine.
The result are failures to feed because the rounds are just not feeding up so the bolt carrier can pick them up, or failures to chamber because of the nose of the bullet is touching the inside front lip. The extra pressure it takes to strip the round out of the magazine, takes away from the force of the recoil spring to push it forward to fully seat in the chamber.
The same problem can be found with some polymer magazines, (nose of rounds touching the front wall of the magazine.) With polymer mags the issue has to do with the thickness of the walls of the polymer magazine body itself. On some polymer magazines the front inside wall is thicker, leaving less room for the tips of the round. This will lead to the same feeding issues as with poorly joined metal magazines.
.223 AND 5.56MM: IT’S NOT ALL THE SAME
Usually if there is an issue with either the front wall being too thick or not enough clearance for the nose of the round to clear the edge it is with military ammunition. The reason for this can be found in the variances between .223 and 5.56mm bullet tips. Although it takes a micrometer to measure, there are slight differences in the length of the rounds depending on their manufacture, bullet weight and type (hollow points, match grade.)
I have a few polymer magazines that the only time I have feeding issues is with military MK262 77-gr ammunition. Even though it’s slightly shorter than your average 5.56 round. MK262’s have a flat tip with a hole in the nose of the round. (The purpose is to help stabilize the round in flight—not expansion like a hollow point.) The MK262 flat tip catches on the front lips of certain magazines leading to chambering issues.
The reason why some brand name magazines do not run well with military ammunition could be that they have been built around and tested using only civilian ammunition. I have used some metal magazines with poorly joined pieces and they still run great with civilian ammunition.
As a soldier, I personally I do not trust or use any magazines that cannot reliably run all types of ammunition. I do not want to have to separate magazines between personal use and ones used for military work.
With today’s modern manufacturing techniques, there should be no reason why magazine manufacturers cannot make a magazine that reliably runs all ammunition they were designed for.
Moving up the magazine the next item to look at are the feed lips. How import are the feed lips? If can have a magazine with a substandard follower chances are it will most likely run for a little while, or at least allow a few rounds to feed before sticking and jamming up. But if you have damaged feed lips you might not get no more than one round off (if that) before seeing feeding issues.
Looking at the feed lips, what is important is how much clearance the rounds have above the front wall of the magazine. If you take a loaded magazine and look at it from the front (looking at the nose of the bullets), the top rounds sitting up against the feed lips, the nose of the rounds should have plenty of clearance above the front wall of the magazine. In particular the first round on the left as you are looking at it from the front, (or the round on the right looking down on it as you normally would.)
If the rounds do not have enough clearance above the front wall of the magazine there is a chance the nose of the rounds can catch or drag on the edge of the front wall of the magazine, leading to chambering issues. The extra energy it takes to strip the round off the edge of the magazine lip, takes away from the bolt properly seating the round all the way in the chamber.
Because energy was robbed from the recoil spring in the loading process, the round will be only partially stripped out of the magazine, with the nose of the round usually somewhere on the feed ramp looking like a chambering problem.
FEED LIP CONSTRUCTION
In regards to feed lip construction, this is where using metal or polymer can make a difference. The biggest issue with aluminum or steel mags is there is a danger of them bending. (Usually from dropping mags on a hard surface.)
This was recognized a long time ago hence there are metal molding tools you can purchase that are designed for to be able to reshape your metal feed lips back into the proper shape and angle.
One benefit of polymer magazines is the polymer feed lips will flex some before breaking. So dropping a polymer magazine on a hard surface there is less of chance damaging the feed lips compared to an aluminum magazine.
Running around in 100 degree
plus temperatures and having to shoot
over an extended period of time (multiple magazines)
the rifle tends to get pretty damn hot.
The down side to polymer feed lips is they can wear out becoming somewhat malleable and allow rounds to slip past them. I have experienced this mainly while serving overseas in hot climates. Running around in 100 degree plus temperatures and having to shoot over an extended period of time (multiple magazines) the rifle tends to get pretty damn hot.
After going through this a few times the feed lips can develop some slight flex to them, allowing rounds to easily slip out. This can lead to double or triple feeds, because they allow more that the one round the bolt is stripping off to pop out into the chamber.
Although I would not say it’s a definitive indicator, but If you store your magazines rounds down in the pouches—which you should for the fastest reload—and you start to find loose rounds at the bottom of the pouch if, it could be a sign of weak feed lips.
It was around 1998 that I first got some of the new (at the time) GI magazines with the green anti-tilt follower. Up until them all our magazines had the black plastic follower, which was basically the same design used since Vietnam.
A note on just how bad some of these black follower military issued magazines were. Prior to any real world deployment I would test fire all my magazines, it always seemed out of a dozen or so, I always had one or two that did not run well. (These I would trash.)
An anti-tilt follower works by keeping the rounds level as they feed up to the top of the magazine. What was recognized with the black follower was (specifically during rapid fire a cyclic full-auto) was the black follower sometimes moved un-evenly up and down within the magazine. This leads to either the nose of the rounds or the back the cartridge hanging up during the loading processes.
Because of this un-even feeding, it can also cause rounds to slip up past the feeds lips during the loading cycle causing double feeds. The good news is just about every manufacturer of magazines today has a version of an anti-tilt follower in their magazines.
To check your followers, simply push down on them with finger pressure. The follower should move up and down smoothly inside the magazine. You will notice some anti-tilt followers have zero play in them and will only go down evenly on both ends, while others might have some play in them. If your followers have a little tilt in them that is OK long as long as you cannot push down one end so far that the follower sticks at a sharp angle and is stuck in the magazine.
I like to hit the magazine catch and the check the ability for the magazine to drop free. Bottom line is if the magazine does not drop free without the need to pull on it, I do not deem it serviceable. With metal magazines if they do not drop free chances are the body of the magazine might be slightly warped or the magazine catch slot might be damaged in some way.
For polymer magazines that do not drop free, diagnosing why can be a little more involved, because of the variances in the thickness and texture of some of the polymer mags.
There are some, depending on how mil-spec the magazine well on your rifle is, that might not drop free at all in your rifle. This is the reason I really like the Magpul PMAG. They were specifically designed to fit the tighter mag well of the H&K 416. Because of this they are guaranteed to fit and fall free in most other AR’s.
METAL OR POLYMER?
Which is better metal of polymer mags? I think both have their Pro’s and Con’s. Personally I prefer polymer magazines for a few reasons. Firstly a lot of polymer type magazines have a window in them or are translucent enough to allow you to see the rounds. Being able to glance down and get a good estimate how many rounds are left in your magazine is great for when you are trying to gauge when to perform tactical reload.
Secondly, and this is minor, but the corners on aluminum mags can be tough on your magazine pouches depending on what type you use. Most polymer mags have soft edges to them, which makes them easier on your pouches.
Lastly, most polymer magazines have raised portions or texturing specifically designed for better gripping—a handy feature when trying to reload rapidly! Regardless which ones you have. As long as you know what quality looks like, if they are well built they will perform well.
PET PEEVES, MYTHS AND WORN OUT MAGAZINES
I have two issues that really bother me that are kind of interrelated even though one has to do with the new GI tan follower magazine. The other an issue you see generally only with polymer magazines. They are interrelated because they both have to do with what a properly loaded magazine is supposed to look like.
Something I see a lot at the range (with both civilian and military shooters), is overloading magazines to 31 rounds. When you cram an extra round in a magazine, there is no give in the tension of the rounds under the feed lips. The result is you cannot properly seat the magazine in the magazine well with the catch locking the mag in place on a closed bolt.
Generally what you end up seeing is a shooter walks up to the firing line, and slaps the magazine in (that stays in place via the catch, but not locked in). Shooter racks the bolt, loading nothing because the feed lips are not seated close enough to the bolt. They pull the trigger and “click”, hammer falls on nothing—and usually the mag falls out because the vibration from the hammer is enough to undo the partial mag catch in the magazine.
While it can be a great source of entertainment to watch a shooter at the beginning of a course of fire pull the trigger on their rifle to only hear a click, it is not something you want in a tactical or defensive situation.
To ensure you do not do this, many will say, “when loading magazines your last round should be on the right.” Here is the problem: with the new “Improved” GI magazine with tan follower, the last round sits on the left. This is counter to just about every other 5.56 magazine on the planet.
Now it’s not that big of a deal if they are the only mags you use, as all the last rounds sit on the left. But what about the Soldier that half of his mags are the tan follower and the others are the older green ones? Now when they are all loaded up you cannot tell by looking at them if they are properly loaded, some will be last round left, some right.
I find this very annoying because one of the signs your magazines are wearing out is if they start allowing a 31st round. So as you can imagine this can get pretty confusing. How does this relate to polymer magazines? There are some (even brand new just out of the wrapper,) that will allow an extra round and will not properly seat on a closed bolt.
As far as I know the GI aluminum magazine with tan follower is the only mag with the last (30th) round sits on the left.
Now moving to some myths. Here are two that both have to do with the magazine spring:
The first is you should only load mags to 28 rounds to ensure they run correctly and you do not wear out the spring prematurely. Second, while shooting from the prone never rest the magazine on the ground or you can cause a feeding issue as too much tension on the rounds pushing down on the spring.
While maybe at one time this may have been true for both, we are talking Vietnam era or Army GI black follower magazines.
The fact is a quality magazine can and should be able to be loaded and stay loaded with 30 rounds for a long time. I have some GI green follower mags from the late 1990s I have used fully loaded on numerous deployments and they still run great.
As far as putting pressure on a mag while shooting prone—using it as a monopod—if your magazine does not work when you do this, it’s because the magazine is worn out or faulty. In fact there are many various aftermarket accessories you can add to magazine base plates specifically giving the magazine a better, stable base while using it as a monopod.
So how can you tell if you have a worn out magazines, aside from loading them up and seeing if you can cram extra rounds in them from the spring getting weak? Really as soon as you start having any sort of stoppages. As I mentioned earlier, the number one reason for most double feeds are the feed lips are getting weak or some follower issue. So whenever I get a double feed I usually just throw away that magazine and be done with it all together.
If you do not have an endless supply of AR mags I suggest numbering all your mags. If you have a double feed, annotate what mag it was and shoot it again. If you get yet another double feed then you definitely know it’s the magazine and its time for it to go!
THE WRAP UP
Whether you are shooting in a match or out on the battlefield, you should not be trusting your reliability based on your Uncles leftover old magazines from the first Gulf war.
Knowing what a quality magazine looks like, and knowing when they are starting to wear out can be the difference between winning and losing in whatever situation you are relying on your AR to handle for you.
Jeff Gurwitch has 25 years military experience—the last 17 with U.S. Army Special Forces. He served in the first Gulf War, three tours both in OIF, and OEF. He has been a competitive shooter for over a dozen years, competing in USPSA, IDPA, and 3-Gun.