Hello, reader. Welcome back to our blog! Today, we are going to talk about upgrading springs in AEGs. Our tech tip series is designed to teach you more about the inner workings of your airsoft guns and equipment. We will show you how to maintain your guns and the potential for various AEG upgrades.
AEGs utilize a spring inside the gearbox to push a piston inside a cylinder. The cylinder is a chamber where the air sits just before being forced out by the piston.
The air that is pushed out drives the BB out of your gun, and the more air pressure there is behind it, the higher the velocity of the BB coming out of your gun. Installing a different spring allows you to achieve higher or lower velocity depending on the spring you put in.
Some electric airsoft guns, as they come from the factory, might shoot harder than your local field will allow, so putting in a weaker spring inside may be necessary. Sometimes, you would want better performance from your gun, so a spring upgrade might be needed to achieve the desired performance.
ASG springs come color-coded for easy identification
How are airsoft springs rated?
Typically, springs will have a rating that looks like Mxxx. The M signifies meters, and the number behind the M denotes the meters per second. Since the sport originated in Asia, they will use the metric system to measure, and of course, we Americans who love to do things our way will use empirical measurements. So, to get what performance you should expect out of the spring, convert that number into meters and feet, and you'll get a rough idea.
An M100 spring = 100m/s = 300f/s or 300fps, measured with a .20 gram BB. This is not exact because different lengths of guns will get more out of certain upgrades due to the cylinder and barrel length and the potential air volume. I have found that, in most cases, these springs are underrated for their number rating, and you can expect 30 to 50 more fps in many cases. Some manufacturers rate their springs by a percentage number, such as 150%. This is rare to see but needs to be clarified. So here's a quick and dirty reference for springs:
You can learn more about what FPS means here.
I think the original manufacturer intended to mean that it is 150% of the velocity compared to an OEM spring, but by whose standards are they using to measure the OEM performance? Either way, if you see a rating that is outside the norm of meters per second, the results will be hard to gauge.
Also, as we as an industry move to chronographing guns in Joules, you'll have to use some judgment on your part to determine what FPS you have to be within when measured on a different weight BB, and then tune your gun based on the older style of measurement.
Irregular Pitch vs. Conventional Coil Springs
Beyond ratings, different types of springs can be had. Conventional springs have the same coil pitch through the entire length of the spring. Irregular pitch springs have varying degrees of coil pitch throughout the length of the spring.
The conventional spring produces the same force no matter where the piston starts in the shot cycle. Irregular pitch springs have varying degrees of tension throughout the spring, making it easier for the motor to cycle no matter where the piston starts from. If the piston is almost entirely compressed back and you attempt to shoot your AEG, a conventional spring would require more torque and battery power to pull the spring back, creating more work/strain on the motor.
Overall, spring length also lowers your fire rate. We have found that in our testing. When installing an irregular pitch spring, the side with more coils at the end should go on the spring guide side. The side with fewer coils goes to the piston side.
The difficulty of working on your airsoft guns
I will classify airsoft tech work into a couple of categories to help you decide what you want to attempt and what you should go to an expert for based on your comfort and experience level.
When upgrading your springs, why not upgrade your piston while you are at it?
ASG Ultimate Polycarbonate Piston
Difficulty
- Minor - This procedure could be done by anybody, and you should do it yourself. As always, ensure you understand clearly and don't force anything, or you could cause damage.
- Moderate - this may require some minor disassembly. If you are not technically inclined, seek help regarding this. Otherwise, you may damage your equipment or cause it to function improperly.
- Major - this requires detailed knowledge for disassembly and should be done by someone experienced. You could cause damage and ruin your equipment if you attempt.
It should be noted that in this day and age of YouTube and information everywhere on the internet, many inexperienced people attempt something in the major category. We implore you not to do that (but you probably won't listen). Many times, we will have a person come in with a fully disassembled airsoft gun that they were not competent enough to work on, so we have to explain that the time we put into fixing that gun has doubled (which makes the labor cost double).
Why? Now we have to assemble a gun from scratch, just get it together, see what is wrong with the gun, then disassemble and work on the gun again to work on the problem the owner originally tried to address. There also might be the issue of parts being missing so that makes the job take longer while people search their bedroom for an elusive spring or screw that may have got dropped during the process. Then, there is the likelihood of damage to components incurred by people forcing parts in or trying to operate the gun in its incorrectly assembled state. Okay, did that scare you away yet?
Regardless of my warnings, you must start somewhere and build your skills. If you have a spare broken gun to turn into a project, that's a good way to start learning. Don't do it on your brand-new gun that someone bought for you with money! You'll be sitting out and not playing as a result! Let's move on.
Let's classify what activities you can do with your airsoft guns.
Cleaning - Minor
The main thing you will do to clean your gun is to clean the inner barrel and lubricate the bucking in your hop-up chamber. This can be done on your own AEG or gas pistol.
Upgrade Your Barrel - Moderate to Advanced
Swapping the barrel will entail field-striping your gun to access the barrel and hop-up system. You will install it into your existing chamber or have a full hop-up ready to go, which you need to put together. It is not the most challenging job, but some guns are difficult to disassemble to get your hop up and barrel out. For example, an M4 style is going to be a moderate job. The front end and possibly gearbox must be removed from an AK-patterned gun to get to the barrel assembly.
Doing something in the gearbox - advanced.
This will require you to take apart the externals of your airsoft gun to reach the gearbox. After that, the gearbox is its beast. The gearbox is assembled with carefully checked tolerances, so if you put it together wrong, you can cause much damage or make your gun perform worse. Critical components that have to be carefully installed and checked are the gears and the piston. Parts are only sometimes dropped in either. Due to the fact that manufacturing tolerances vary from manufacturer to manufacturer, plus the difference in specs between gun brands for the same style of gun, this adds a lot of variables.
Quick-change Spring - Moderate
Working on a gun with a gearbox with this feature is essentially halved. You might still have to take the gearbox out of the gun body, but you can change the spring without opening it, and you could easily reverse it if the gun is not optimized to run the spring you put in there.
Quick-change Spring for ICS gearboxes - Minor
Sometimes, spending a little more upfront pays off! The ICS split gearbox means you can open your M4 like a real AR and access the spring within seconds. You do not have to remove the gearbox from the gun to do it!
