In recent years, the firearms industry has made great progress in polymer mags, and they’re better today than they ever have been. However, there are still some problems that exist, so I’ll go over the most common problems with magazines and how to fix them.
I’ll start by doing a quick overview of each problem, before diving deeper into what causes the issue and how you can fix them on your own.
|Mag Not Seating
|Gets better with time, use more force to insert magazine
|Mag Rattles When Loaded
|Spring tension offset, try hitting back of the magazine
|Mag Falls Out While Shooting
|Tolerance issue, replace mag + mag catch or have gunsmith fix slide
|Mag Won’t Drop
|Magazines swell when full, try cleaning the internals
|Can’t Fully Load Magazine
|Mag springs loosen overtime, try underloading mags until then
If you read through the table, you can see that most issues can be fixed by cleaning, using more force, or breaking in the magazines. Of course, these don’t solve every issue, but they go a long way.
Next, I’ll go over each issue individually with what causes the problems, and how to fix them.
Magazine Not Seating
You can fix a magazine that is not seating by using more force to insert the it until it’s worn in enough to function as intended. Otherwise, try leaving out one round when you load to avoid overburdening the magazine spring.
When magazines or almost anything else is new, they often need to be broken in a bit before they function perfectly.
What causes this issue is likely the polymer of the magazine being too large, and not allowing the mag to get to where it needs to be in order to seat and click in.
This can easily be fixed by slamming the magazine into the gun when you are loading it. Don’t be afraid of damaging the gun, they are built well and this is very unlikely. They’re made to stand abuse, and arguably, they’re made to have the mags slammed in.
Once you've slammed your mags in, you’re ready to start shooting. While you shoot, you should be tracking your shot groups with Range Notes, which is a notebook that we put together that’ll get you shooting better groups. Check it out!
Over time, this will shape the magazine to be able to seat properly every time, without excessive force.
Magazine Rattles When Loaded
Magazine rattle is caused by the spring tension being offset, freeing rounds within the magazine. This can be fixed by applying force to the back of the magazine when it is loaded, which should settle the rounds and stop the rattling.
This isn’t a big issue, but it could get annoying. This is especially common in double stack magazines because force is being applied to both sides of the stack of rounds.
If the tension of the magazine spring is just in the right spot, it can allow a round or two inside the magazine to have the freedom to move back and forth. Again, not a big issue, but likely not something you want to have happen a lot.
To fix this, try slapping the back of the magazine. This should jiggle the rounds and spring around, and shift tension to a location where the rounds won’t be free to move.
Magazine Falls Out While Shooting
Magazines falling out while shooting is likely caused by bad tolerances causing the slide to hit the magazine and force it out when the slide cycles. If this is the cause, the slide needs to be sanded or lightly milled to have the correct tolerances.
I’ll start off with a disclaimer; this one is about handgun mags, and more specifically, Glocks.
This is a hard issue to diagnose, and not necessarily easy to fix even if you manage to narrow down the cause. It’s possible that this issue is caused by a bag magazine catch/release, and I’d start by replacing them because it’ll be the easiest and cheapest option.
This isn’t the most likely issue though, because if the mag falls out while you’re shooting, it means the mag catch was working properly before you started shooting.
If you try the mag catch solution and it doesn’t solve the problem, it’s most likely an issue with your slide. If the tolerances are off by just enough, when the slide cycles it can slam against the magazine, pushing it out of the gun.
Some people have fixed this by sanding down the inside of the slide where they think the problem is occurring. While this works, I can’t recommend that you do it unless you really know what you’re doing.
If you think this is the problem, try sending it to a gunsmith, who will be able to diagnose and fix the problem without causing unnecessary damage to your gun.
Magazine Won’t Drop
Magazines not dropping can be caused by swelling when the magazine is fully loaded. The amount of swelling can be influenced by humidity, temperature, and debris inside the magazine. You can try to fix this by cleaning the outside and inside of the mag, as well as the gun itself.
This one is a little tricky. Many mags are drop free, which means that loaded or not, they’ll drop from your gun when the mag release is pressed without any extra force. I have another article about drop free mags, check that one out next!
Some magazines are not drop free, and need to be pulled out when the mag release is pressed.
Either way, naturally, magazines swell up when they’re loaded because of all the added pressure inside. In the right conditions, this can cause enough pressure that they won’t drop out of the gun on their own.
This can also be made worse by certain weather conditions, like humidity and temperature.
Another potential cause is dirt. If your magazine is swelled up and dirty, it’s likely to start sticking. Try cleaning the outside and inside of your mag as well as the inside of your gun.
If that doesn’t work, try using the mag in different environments, and if that doesn’t either, you might just have a non drop free mag and will need to buy a new one if you want it to drop out on its own.
Can’t Fully Load Magazine
The inability to fully load a magazine is common when mags are new. Before they’re used, the springs haven’t had time to wear in and will need to be broken in. Try underloading the magazine until it’s had time to adjust to the pressure.
This is a common issue for new magazines and has a fun solution: shoot your gun more.
New mags are notorious for their stiff springs, and just need some time to wear in. Trust me, it will get easier with time.
Until they’re broken in, you can underload your mags by a round or two. This will alleviate the frustration of trying to get the last round in, while still wearing in the magazine spring.
Magpul Magazine Problems
This isn’t a huge issue, and I wasn’t able to figure out the exact problem, but enough people mentioned that this was an issue so I thought I should mention it myself; Magpul mags seem to have issues with steel case ammo.
I’ve heard multiple stories about Magpul mags using steel case rounds not loading properly. I can’t prove it or figure out the cause, but it’s something you should be aware of if you have Magpul mags and are planning to use steel case ammo in them.
The Bottom Line
The bottom line is that most issues with magazines can be fixed by using some extra force, cleaning your weapon, breaking in the magazine, or getting a new one.
Thankfully, mags are pretty cheap and if they’re broken, they’re not difficult or expensive to replace.
Again, don’t worry about damaging your gun if you want to try slamming in mags. Most firearms and accessories are built to last and sustain force, so it shouldn’t be a problem.