Airsoft Gas Blowback Maintenance Guide

A Gas Blowback ("GBB") is a type of airsoft or pellet gun that uses compressed gas—typically green gas or CO2—to cycle the action of the gun, providing a more realistic shooting experience compared to spring-powered or electric guns. That being said, maintaining the replica is crucial for its longevity. Think of it like changing the oil in a car—if you don’t maintain it, you’ll run into problems.

Gas Types and Their Impact on Maintenance

The type of gas used will slightly impact the maintenance schedule. Before diving into maintenance specifics, let's break down the most common gas types used in gas blowback pistols (GBBP):

1. Green Gas and Variants (Most Common)

Green gas is the most popular and widely used propellant for GBBs. It consists of propane mixed with a small amount of silicone oil. A can typically costs between $15 and $30, depending on the size.

For players requiring higher pressure, Red Gas and Black Gas are alternatives. These are usually composed of 97% propane and 3% silicone oil. Some players opt for camping propane as a cost-effective alternative since it lacks silicone oil, but this choice directly impacts maintenance intervals and performance.

The gas you choose plays a significant role in both performance and upkeep. Green gas provides a balance between power and convenience, offering consistent performance with manageable maintenance needs. However, over time, the buildup of silicone oil and general wear on internal components must be addressed through regular cleaning and maintenance.

In contrast, Red Gas and Black Gas offer increased power and recoil but place additional stress on internal parts, accelerating the wear of seals and o-rings if not properly maintained. Players using high-pressure gases should perform frequent maintenance and lubrication to prevent issues caused by increased wear.

For those using camping propane, the cost savings are significant, but since it lacks silicone oil, maintenance becomes even more crucial. Without proper lubrication, internal components can experience excessive friction and wear, potentially shortening the gun’s lifespan. However, with frequent and proper maintenance, no unusual wear should occur.

2. CO2

CO2 (Carbon Dioxide) is a colorless, odorless gas known for its higher pressure, making it well-suited for cold environments. It also boasts excellent energy density for its size and is a budget-friendly option, with each canister costing around $1.50.

CO2 is most commonly found in pistols, though some rifles also accept CO2 magazines. One advantage of CO2 is its affordability compared to other power sources. Unlike electric airsoft guns (AEGs), which require rechargeable batteries, CO2 cartridges provide a consistent power source without frequent recharging.

A typical 12-gram CO2 cartridge delivers approximately 50 to 60 shots, depending on the airsoft gun’s design, usage, and ambient temperature.

Essential Maintenance Items

To properly maintain a GBB, it is recommended to have the following items:

  • 70% or 99% isopropyl alcohol (for cleaning internal parts)

  • Alcohol wipes (for quick cleaning)

  • Lint-free paper towels (to avoid residue buildup)

  • Cleaning rods (rifle-length rods can clean both rifles and pistols)

  • Silicone oil or spray (for lubricating moving parts)

  • Super Lube 21030 Multi-Purpose Synthetic Grease (Grade 2) (for o-rings and seals)

Regular maintenance will help ensure your GBB performs reliably and extends the lifespan of its internal components.


Gas Pistol Maintenance 

For gas pistols, I recommend cleaning, re-oiling, and greasing all necessary parts every 3-4 game days to ensure optimal performance and longevity.

Maintenance Procedure

  1. Learn how to field-strip your pistol

    • Example: WE G17 G5

First, let’s clean the inner barrel. When cleaning, make sure to use a spinning motion while pushing the cleaning rod in to ensure all dirt and grease are removed.

  1. Start by cleaning with alcohol pads.

  2. Follow up with a lint-free paper towel.

  3. Run as many passes as needed until the paper towel or alcohol pad comes out clean.

Once finished, proceed to the next maintenance step.

Second, pull the nozzle fully forward until it stops, then spray a 1-second burst of silicone oil in the marked area.

After completing the two steps above, you can reassemble the slide.

Now, let's move to the lower frame.

First, clean off as much grease and oil as possible using paper towels or alcohol wipes. Then, spray a small amount of oil on each designated spot.

Last but not least, use a small paintbrush to apply a thin, even coat of lubricant on the metal rails where the slide makes contact. There are four areas on the WE G17 G5, as shown here.

Afterward, reassemble your replica. Your WE G17 G5 is now maintained and ready to use. Rack it a few times to ensure it feels smooth and free of any gritty sensation.


Rifle Maintenance

General Intervals

  • It is recommended to clean the inner barrel and re-grease the bolt carrier group every 3,000–4,000 shots.

  • For new guns, perform the first two maintenance sessions more frequently to ensure proper break-in.

Troubleshooting & Maintenance

  • If the nozzle on your bolt carrier group sticks or doesn’t seal properly, disassemble the carrier group, clean it, re-grease it, and replace any necessary parts.

  • If your replica is new or doesn’t cycle smoothly, and if it sticks often, disassemble the fire control group, clean it, and re-grease it.

Field Stripping

  • To maintain a rifle properly, you must know how to field strip it. If you're unsure, look for videos specific to your replica model for guidance.

For this guide, we will be using the Viper Tech MK18 as an example.

First, push the rear takedown pin to partially separate the upper and lower receivers. Then, swivel the upper receiver forward using the front pin as a hinge. Finally, push out the front takedown pin to fully separate the two halves.

Pull the charging handle back, allowing the bolt to come out first. Then, slide the charging handle all the way back and pull it down.

Using paper towels and alcohol swabs, clean all the greasy surfaces on the bolt, charging handle, and receiver. A toothbrush can help with cleaning the receiver more effectively. 

Then, use grease and apply a thin film on the bolt and any areas with metal-to-metal contact. Be sure to use a very thin coat of grease, as applying too much can impact the smoothness of cycling.

Finally, clean the inner barrel with the cleaning rod and alcohol pads. Reassemble the bolt and charging handle. If you have difficulty disassembling your specific replica rifle, search for videos of your model for guidance. We're only covering M4 gas blowbacks here, and even though there are slight differences between models, the general process is similar for most AR-style rifles.