What is a Mid Cap Airsoft Magazine? – Beginners Guide

As A beginner in Airsoft there is a lot to learn when starting out and a lot of unfamiliar words that airsoft players who have been playing for a while throw around. One of these words is Mid Cap Mag. On this post, I will try to answer this  question like a complete beginner, what is an Mid Cap Airsoft Magazine?

A Mid Cap (or Medium Capacity) Airsoft Magazine is the device that stores airsoft BBs and is attached to an airsoft gun to feed the BBs into the Gun. The thing that distinguishes a Mid Cap Airsoft Magazine from other airsoft magazines is the fact that this mag uses a spring that does not need to be wound up as the BBs get used up. You feed it once and use it until it’s spent. The mid cap mag has the greatest level of realism in airsoft since it simulates how real firearm magazines work. Let’s delve deeper and see how this mag works and what that means for you as a beginner airsofter.

How midcap mags work

A Mid Cap Airsoft mag has a tight spring that pushes bb’s constantly into the airsoft gun. The mag spring maintains its tightness even as the magazine is spent. this creates a constant flow of bb’s without having to wind up the spring as the mag is spent.

Here is a video that helps to illustrate how the mag works

This mechanism ensures that you do not have to wind up your mag spring in order to ensure that your bbs are still being fed efficiency into your airsoft gun.

The other great thing about it is that it does not make any noise at all since its spring remains wound up at all times. .

The difference between a mid-cap mag and a hicap mag


An average Mid Cap magazine holds about 100-150 bbs while the average hi cap mag holds about 300 bb’s. The reason for this is because the midcap mags does not have a lot of room to store a lot of bb’s since it uses a spring system to push the BBs out of the mag.


Hi cap mags how the characteristic rattling that happens when the mag starts getting spent. on the other hand, the mid cap mag does not have this challenge since the BBs are fed using a spring system that holds the BBs in position without them rattling around.

Ease of loading

You need to use a speed loader when loading a mid cap mag but you can just dump the BBs into a hi cap mag and you’ll be ready to go.

The downside to the mid cap  in this respect is that you will need continue winding the gear at the bottom of the mag to ensure that its loading bb’s correctly into the gun.

Construction Material

Most midcap airsoft mags are constructed using plastic. On the other hand most high cup mags constructed using metal.

Feeding efficiency

Hi cup mugs tends to miss fire alot since they do not consistently feed the airsoft gun with BBs. On the other hand, most midcap mags feeds airsoft guns very efficiently.


Midcap mags are the most realistic since they hold a limited number of bb’s and they do not have a rattling sound when using them. You also don’t need to think about the mag once you load it until it’s spent.

When should I use a midcap mag

A midcap mag would  work with best for you if you are looking for realism. They offer the greatest level of realism in airsoft since it does not rattle and the bb rounds are limited since the number is not an insane amount.

Mid cap mags will also work for you when you do not want to think about the mag once you load it on the gun. Unlike the highcap mag that needs to be wound up once to enable the BBs to load into the airsoft gun, once you fix the mag on the gun, you don’t need to think about it intil its spent.

The best midcap mags

KWA K120

During my research, I found this mag to be the most widely recommended mid-cap mag out there.

It feeds 120 bb’s and is popular for being really reliable and durable.

Check it out on Amazon


I also found the PTS EPM to be a good midcap Airsoft Mag. You can check it out here on Amazon.

How to maintain a midcap mag

Even the best midcap airsoft mags can run into problems over time. To help the mags have the longest lifespan, its best to do the following things to ensure that the mags are well maintained.

During my research, I found this video that does a great job of describing what you need to do to maintain your midcap mags.