Airsoft ammo might just be the least “cool” piece of necessary equipment that airsoft players need to deal with daily. Propellants give it a run for its money, but it’s actually one of the most vital considerations you can make when you’re evaluating a purchase.

You can spend well over a thousand dollars on a tricked-out, sleek, sexy airsoft AEG, and without the right ammo, it’ll be like putting diesel fuel into a Dodge Viper. That is, it won’t be good. It won’t be accurate, it will lack range, and it might not even fire at all.

What good is a cutting-edge Trijicon red dot sight that’s capable of producing tack-driving groups if the ammo itself is not capable of producing tack-driving groups? As you might have guessed, not very much good at all.

The operative point here is that airsoft ammunition matters, just as much as the airsoft gun itself, and just as much as all the fancy attachments you add to it.

This guide should help you get a better handle on what ammo you should use. It will at least lay the groundwork to enable you to evaluate ammo on your own.

Size in Airsoft Ammo: A Make or Break Feature

Size in airsoft ammo is not the only feature you need to evaluate, but by virtue of the fact that any given airsoft gun can only take a certain size or certain sizes of ammo, it is the first and possibly the most important condition you need to consider before buying.

Just like a rimfire rifle can’t chamber or fire centerfire cartridges, airsoft guns will take specific sizes in airsoft BBs and ammo. We can perhaps best illustrate this point with an example.

Visit our listing for the G&G CM16 Raider-L M4/M16 AEG, which is one of the more popular platforms in the game today. Scroll down to the product specifications and you will see under the barrel specifications that the barrel is “357mm, 6.03mm tight-bore.”

While the size of the ammo this rifle takes is not clearly listed, it can be gleaned from the description that it takes 6mm airsoft BBs. This is fairly common, and many airsoft guns on the market today take 6mm BBs.

A good bed is that your airsoft gun takes 6mm BBs for this very reason, but there are other sizes of airsoft BBs out there. For example, some airsoft guns take 8mm ammo. Guess what will happen if you try to load 8mm ammo into an airsoft gun that takes 6mm BBs. If your guess was “nothing will happen,” you are more or less right!

Check the product specifics before you buy ammo, and if you can’t tell for sure, don’t waste your time guessing. Call us at 800-581-6620 and we’ll tell you what size ammo you need for a given platform. We’ll even make specific recommendations for performance.

What about Airsoft Ammo Weight?

On that same page, scroll a little further down to “Muzzle Velocity.” You will see that it reads “370-400 FPS with .20g projectiles.” This means that this AEG is capable of producing muzzle velocities of nearly 400 FPS with .20g airsoft BBs; however, this does not mean that .20g BBs are the only projects it can fire.

In fact, there is great variability in airsoft BB weight, and it's one of the features that will most impact performance, accuracy and power. An airsoft gun that can shoot 6mm BBs can shoot ammo of all different weights. Holding all else the same, here’s what you need to know.

-.12g ammo

Airsoft ammunition with a weight of .12g is one of the most common types you can buy. However, you will notice that there isn’t a space for it listed in our menu, and this is because “shelf grade” .12g ammo is usually very low quality. Also, this type of ammo is very light, so it usually doesn’t follow a predictable trajectory. You should generally avoid these.

-.20g ammo

.20g ammo is also very common, which is why that G&G CM16 Raider AEG uses it as a baseline. They’re easily available and also generally pretty low price, so you won’t feel too bad burning through thousands if not tens of thousands of these.

-.25g ammo

Because .25g ammo is heavier than .20g ammo but basically the same size, this gives it a higher density. As a result, .25 ammo usually has better range because it is also able to “cut through” the wind. Also, since it is heavier, it carries more energy and hits harder.

-.28g ammo and .30g ammo

Heavier and more stable than .25g ammo, both .28g and .30 ammo are popular choices for serious players. These weights in airsoft ammo have fairly stable trajectories and can achieve decent ranges. Some players also like to use them with airsoft sniper rifles for these reasons.

-.40g ammo

One of the heaviest readily available sizes in ammo, .40g ammo has a stable trajectory, flies far, and hits hard. This makes this size popular with airsoft snipers.

-.45g ammo

One step above .40g ammo is .45g ammo, which is more than another 10% heavier. As a result, FPS ratings will drop slightly, but .45g ammo still has food range and a stable trajectory over long ranges, making it popular with airsoft snipers.

As a general rule, as weight increases, so does density, which means that the FPS rating will drop while power increases and stability in trajectory increases as well. You can usually see recommendations on each airsoft gun product page, but if you want more suggestions, give us a call.

Quality of Construction

Quality of construction is another big factor that impacts the performance and practicability of ammo. Purchasing ammo that is the right size for your airsoft gun is imperative, as is testing out a few different weights to see which weight performs best in your airsoft rifle or airsoft pistol. However, you should not be motivated by price alone, because cheap airsoft BBs usually come with a couple of crutches, including the following.

One of the biggest problems associated with cheap and low-quality ammo is that it often features flaws in its construction, such as the fact that some ammo is molded together and will feature prevalent seams. Seams are a big problem in ammo for two reasons.

One is that seams create an imperfect, inconsistent surface, which will impact trajectory. If the BB is not as close to “perfectly round” as possible, the airflow over the projectile will not be even and it will cause yawing or shifting in flight.

These seams can also cause cheap ammo to break apart in the hop-up chamber or in the barrel of your airsoft rifle. The best-case scenario this causes is a headache; in worst-case scenarios, this phenomenon can cause expensive damage to your airsoft gun.

Other cheap ammo may appear to be “perfect” but may be poorly polished or unevenly or inconsistently weighted. Aberrations in the internal density of an airsoft projectile may be invisible to you, but they will result in inconsistent trajectories, varying ranges, and poor accuracy.

For these reasons, you need to be sure of what you’re buying or the performance of your ammo will be good ammo. Remember, if you have any questions, we are always here to help you choose the best options and secure the best quality.

Are there Any Other Features that Matter?

Besides size, weight, and objective quality in airsoft ammo, there are some other features you could shop for that can lend you additional performance, which is covered by some of the following.

-What about color?

The short answer here is that color doesn’t really matter in airsoft ammo, but color can be used by players to make them more effective in a match for a few reasons.

For one, using white or light-colored BBs makes tracing shots easier. That might be something you want in order to tune your airsoft rifle at the range. It also might be something you want to stay away from, for example, as an airsoft sniper, where you want both yourself and your shots to remain hidden. Dark-colored BBs might be much more practical for this.

-Tracer airsoft ammo

Tracer ammo is usually just ammo that glows in the dark, so that you can see exactly where your shots go in dark settings, such as at night or in close quarters inside. These serve as a type of “pseudo” incendiary tracer that lets you direct shot placement without the use of sights.

There are also tracer units you can buy for your airsoft gun that actually create more “glow” and make it much easier for you to see where your shots are heading. They’re excellent for reflex shooting and just downright cool.

-Biodegradable ammo

Biodegradable BBs are also frequently known as “bios” and are made from a combination of natural products and other biodegradable materials. They cost more to manufacture than regular plastic BBs and so they are more expensive; however, conscientious players use them in preference to standard BB pellets. In addition, some outdoor fields and courses may require players to use them because a field would quickly become littered with pellets otherwise.

-Other types of ammo

In addition to tracer ammo and biodegradable pellets, there are also a few other forms of ammo that are worth a mention. Some of these are marker ammo which might also be called “dust” ammo. These types of rounds are covered in chalk, powder, or dust and release a little puff of smoke when they strike something. This makes identifying a connection easier, and it also leaves behind a little mark so you can see if or where your shot landed. These are also useful for sighting in airsoft guns because you can see where on the target your shot has struck before you make adjustments.

While You’re Here…

Airsoft ammo is not the only item about which conscientious airsoft players should be well informed. You should also deck yourself out with some of these useful accessories.

-Pick up some spare mags

One mag is not enough, and hopefully, no one has ever claimed otherwise. In the heat of a match, you need to be ready with several spare loaded mags that you can keep right on your vest. If you ever run out of ammo, you’ll be glad you kept a spare loaded mag within easy reach.

-Get ready with a speed loader!

A speedloader is also an invaluable accessory to bring with you into a match. During down periods when you have time to regroup and recover, you’ll want to replace any headroom you have in mags you’ve been emptying.

Good luck with that, unless you have a speed loader on hand. We carry plenty of these in our online shop. Pick up one or two even and throw them in your vest till you need them.

-Add some airsoft ammo storage pouches to your vest

Carrying spare mags will help you be better prepared. Carrying a speed loader will help you replenish fired rounds, as long as you were conscious enough to bring along spare ammo.

Don’t carry it in a bottle. Bring along one of the collapsible ammo storage pouches that we sell here. They’re big (some hold as many as 3,000 rounds), they’re MOLLE-compatible, they feature tough construction, and some of them are even collapsible, saving you space when they run empty.

Armed with this information, you should be fully ready to go out and pick up some ammo that will work ideally in your favorite airsoft gun, but don’t feel like you need to go about it alone.

There are a lot of fine details to evaluate, and we can put our experience to work for you. Give us a call at 800-581-6620 and we’ll be more than happy to walk you through how to choose ammo that would perform accurately and reliably in your airsoft rifle or pistol. We’ll even make specific recommendations.