Does Inner Barrel Length Matter? (Accuracy and Range)

The long inner barrel on an airsoft gun

Inner barrels are among the most important fundamental parts of any airsoft gun regarding the type, so if something is wrong with it, the whole gun suffers.

The question is, how much does the length of an inner barrel matter for accuracy and range?

The length of the inner barrel doesn’t matter as long as the barrel isn’t too short or too long, so it ideally should fit between 200mm and 455mm. The longer inner barrel length won’t make the gun more accurate by default, yet the quality of the build will.

How does the length of the inner barrel matter?

The longer the barrel the higher the odds of malfunctioning as there’s more room for something to go wrong as there is more room for mistakes in build, scratches, and dirt which also results in more maintenance.

If the barrel is too long (above 455mm) the gun may even lose some accuracy as the airsoft gun may lose compression force on the way. So, you’ll find longer barrels on higher velocity guns such as DMRs and snipers, yet even if the barrel was shorter on such guns it wouldn’t affect the accuracy.

The main purpose of inner barrels is to stabilize the BB and if the barrel is too short it can’t do that, while once the stabilization is achieved the barrel doesn’t need to be any longer.

There are more things that affect the accuracy of your gun, so let me answer some common questions and let me explain how you can achieve the best performance with your airsoft gun.

What affects the accuracy and range the most?


Hop-up is part number one that is directly correlated with the effective range of your airsoft gun. This means that a good hop-up will make your gun accurate at a long distance and only become inaccurate by the very end of the maximum distance it can reach.

The gun with great range but poor hop-up may actually have a terrible effective range because although the BB can travel like 200 feet, it’s accurate at 140 feet after which it loses the trajectory and the extra range it can travel is pointless.

A good hop-up (like Madbull) will easily make the BB land at the desired spot even with mediocre FPS, so it’s impossible to compare real guns which depend on the generated velocity and have rifled barrels as airsoft guns are simply different and the same logic doesn’t apply.

Air compression

Leaking is always associated with losing something precious which could otherwise be used to improve the overall performance and in this case, it’s the air that pushes the BB.

Airsoft guns are not perfectly compressed by default, especially the budget ones, so sometimes a few fixes that will make the compression firmer can mean the day and the night in performance.

Air compression affects the entire gun, so it’s not necessarily one part that needs to be fixed though!

Quality built inner barrel

This is the point of the article, quality build, and a polished, dirt and scratches-free inner barrel is all you need. This can be considered a very fundamental thing, so once you are sure the barrel isn’t a problem and you want to improve the performance of the airsoft gun, look for other upgrades first (like hop-up).

This is among the reasons why I believe that the stock inner barrel doesn’t need to be replaced in the first set of upgrades.

Heavier BBs

Sometimes the simple switch from light to heavy BBs will bring you the desired accuracy as heavier BBs are directly correlated with effective range.

Heavier BBs maintain the velocity throughout the entire trajectory better than lighter ones, so you can expect that the BB will be more stable and have a higher velocity at, for instance, 100 feet than the lighter BB. Logically, this means that after 100 feet the lighter BB will carry less power and will start to deviate in trajectory.

This is especially a case on a windy day, as even the slightest dash of the wind can mean a nightmare for a BB and carry it away.

Does barrel length increase FPS?

Barrel length only increases the FPS in gas guns as the gas has more room to expand and propel the BB. In other gun types, barrel length won’t affect the FPS, but switching to a tight bore barrel might increase the FPS from 10-30 FPS as it will cause a better seal, so the air pressure will be higher behind the BB and thus the BB will gain more traction.

So, if you own a gas gun, a longer barrel may increase FPS by 10-20 on average, and on any other gun, it simply doesn’t matter as long as it’s not too short.

FPS is also not directly correlated with accuracy as the low FPS gun with a nice Hop-up can outshine any powerful airsoft gun with a poor hop-up unit.

However, more FPS means better support for heavier BBs and more pain for the people receiving a hit on the other side.

Is it better to have a longer or shorter barrel?

An unnecessary long inner barrel is more of a pain than something useful. Be careful that the inner barrel doesn’t outreach the outer barrel as it can get damaged on impact and it can lower your gun’s accuracy. Moreover, it’s aesthetically unpleasing to see inner barrels sticking out, so in either case, use a right-length inner barrel or try to cover it with a suppressor.

Long barrels are also annoying for CQB games as the longer barrel means worse target acquisition at close range, lower mobility and it’s challenging to take covers while the enemy also has an easier time at spotting you.

So, shorter barrels are ideal for CQB scenarios while guns with longer inner barrels are better for outdoor games.

This will be by default as most CQB limit FPS guns don’t come with long inner barrels, and DMRs and snipers are not seen in these games.

What is the best barrel length for accuracy and range?

In my opinion, you should aim for any barrel between 200mm and 455mm that fits your gun, but look for quality as the barrel’s primary function is to stabilize the BB and keep it in the right direction until it leaves the gun.

So, go for proven brands and don’t compromise the built quality as cheaper inner barrels from questionable manufacturers tend to have tiny imperfections which will interfere with BBs trajectory and dramatically decrease the accuracy.

In other words, length doesn’t matter but the quality of the build does.

TIP: A simple inner barrel polishing may make your shots more accurate. You’d be surprised how many people don’t maintain their guns properly and think they need to change whole parts while simple cleaning or lubing is all their guns need.

Can you cut an airsoft inner barrel?

It’s possible to shorten the airsoft inner barrel by cutting it using a lathe or a combination of a pipe cutter and a drill. In either case, you’ll also need to crown it as there will always be imperfections when you cut it at the top and the BB might stuck. It can be tricky to do it on your own if you don’t own the tools, and if you are not careful you might damage the barrel from inside which will absolutely affect the accuracy.

If you feel comfortable you can do it, but the airsoft workshops can do it for you and inner barrels aren’t that expensive so it might be better to simply buy a new one unless you already own an expensive high-tier one and only want to trim it a bit.


Dino is a thrill seeker who loves to share what he learns about his favorite hobbies.

Recent Posts