What is a GBB Airsoft Gun?

GBB is short for “Gas Blow Back” and just means the system will propel a BB as it cycles a slide/bolt which then loads the next shot. You can break down a single shot as such: once the TRIGGER is pulled, compressed gas is released from the MAGAZINE, flows through the HOP UP UNIT, and pushes the BB out of the INNER BARREL. The same gas from the shot is used to push the SLIDE back, and the RECOIL SPRING drives it forward while the NOZZLE loads the next BB into the HOP UP. Like with my previous explanation of AEGs, there are additional parts involved, but this is the simplest breakdown to create a good foundation.


G&G Armament GTP 9 Black	G&G Armament GPM1911 CP

Again, don't worry about the details. All you need to worry about at this very moment are: GAS PROPULSION, HOP UP, BBs, and MAINTENANCE.

Gas Propulsion

Gas Blowback Airsoft Guns have no batteries, no motors, no gears. It is all compressed gases and release valves. The gas does matter in more ways than one: it will determine FPS, rate of fire, reliability, and even how often you need to do maintenance. With this said, GBB Systems will primarily run on one of three sources for propulsion: Propane, “Green” Gas, and HPA.

Propane

This is no different from your everyday bottle of camping propane. As the cheapest option, all you need is to purchase a fill adapter and you are on your way, with a couple of caveats. Propane in these cans are stored at a higher pressure than with green gas cans. This means there is a lot more unnecessary wear and tear on the moving systems, shortening the overall lifespan of the system. Propane is also considered a “dry gas,” lacking any lubrication that will ultimately dry out your system. Lastly, the smell of propane can be off-putting. Typically odorless, a safety additive is added to propane for leak detection. Some fields even ban them because of the overbearing sulfur smell that can fill up a room quickly, so check with your local field before investing in these cans. Though functional, it is best to avoid propane as your main gas source and look towards the more modern Green Gas.

Green Gas, Red Gas, Black Gas

The drawbacks of propane created the need for something better, which came in the form of Green Gas. These are all propane based gases with a lubricant additive and less of the smelling additive. The added silicone oil prevents drying out as it spreads through the system with every shot. Green gas is considered the standard for Airsoft GBB and what most FPS ratings are based on. For an extra punch you can look into the higher pressure variants in Red and Black Gas. Why use higher pressure gas? Higher FPS, faster cycle time. Again, this will cause extensive wear so keep some spare parts handy if you look to go this route.

HPA (High Pressure Air)

Growing in popularity in the indoor airsoft scene, HPA utilizes an air tank filled with compressed air to power the system. HPA stands for just that: “High Pressure Air”. A pressure regulator on the tank even allows the user to dial in the perfect FPS. With no cans of green gas to deal with, the bigger the tank, the more shots you get. Keep in mind that this has the most expensive barrier to entry. You will need to purchase an air tank, regulator, hose, and each magazine will need to be fitted with an “HPA Tap.” Speaking of the tank, you will need a way to lug it around, be it a backpack or what have you. Before going down this path I suggest you try the other systems first.

HOP UP: Firing a Straight Path

Hop Up will always be important and worth mentioning again and again. It is what sets Airsoft apart from every other precision shooting sport. A rubber bucking puts pressure on a BB and creates a backspin as the BB is shot through the barrel. The level of pressure determines the backspin and the more pressure, the higher the trajectory. Finding the right amount of the pressure (or Hop) will result in a straight flying BB that glides through the air.

Hop Up and BB Flight Path

There are many ways Hop Up can be adjusted on GBBs, but today we will focus on pistols. Some GBB pistols require the slide to be removed in order to access the Hop Up dial. Others, like the G&G GPM92 or GPM1911CP, come with a Hop Up tool that uses the barrel to adjust the level of Hop. The G&G GTP9 even goes so far as to store the tool in the grip itself, providing more freedom for on-the-fly adjustments. Ease of adjusting Hop Up can help steer you towards your next GBB pistol, so be sure to reference your user manual for the best approach to adjusting your Hop Up.


G&G Armament Piranha Mock Round Hop Tool	G&G Armament GTP 9 Hop Up Tool Included within the Grip

BBs: So Nice They Named it Twice

Like before, your choice in BBs is one of the most important decisions you can make in this sport. The golden rule for your new GBB is to BUY QUALITY BBs. Look for smooth, premium BBs. You can tell by just looking at them. They should be polished smooth with no bubbles or inconsistency in texture. ANY BB that is semi-transparent, brightly colored, or under 0.20 gram in weight should absolutely be avoided. Failure to do this will cause damage to almost every aspect of your brand new GBB. The BBs will shatter, causing jamming, scratches, and will ultimately break your replica. In addition, do not use BBs that have already been used or have been sitting on the floor. The dirt on them will cause jamming and accuracy issues.


G&G Armament Perfect BBs 0.20g (5600r/Bottle)	G&G Armament Perfect BBs 0.25g (5600r/Bottle)	G&G Armament Biodegradable BBs 0.20g (5600r/Bottle)

Over 99% of Airsoft BBs come in one shape and size—6mm spheres. How they differ is determined by weight and material. As stated before, the lowest weight you should use is 0.20 grams, but weights can go up as high as 0.40 grams or higher. Lower weight BBs use less dense material and as a result tend to be cheaper, whereas higher weighted BBs benefit in outdoor applications as they are harder for wind to push off course. Most BBs come looking polished and white, but material composition can change more than just color. They can even be infused with a glow-in-the-dark material, and when paired with a tracer unit (sold separately), shine streaks of light across the field. Playing outdoors? BBs made out of PLA add a biodegradable element to reduce your environmental impact as you play. At the end of the day, choosing the right BB for you can be just as important as the gear you wear.

MAINTENANCE: Keep on Going and Going

Saving the best for last is an understatement when it comes to this category. With proper maintenance, you have a clean working gun for a long time. I cannot express enough the importance of maintaining your GBB. This system has moving parts exposed to dust, dirt, and moisture. It is pushing air through and over seals that can dry and crack. Built-up debris can gunk up your system and cause misfeeds, drop in accuracy, and even permanent damage. With this said, let’s get to it.

The first step is to remove the magazine if you have not already done so. Next you need to refer to your manual for take-down instructions. Every pistol can be different in the takedown procedures, and listing each one would take too much time.

GTP 9 Takedown Process

Now that you have the pistol broken down you can begin the cleaning process. Use microfiber or paper towel to wipe down all reachable surfaces. No need to scrub, you are just trying to remove the dirt and oil that builds up with normal use. Be sure to focus on surfaces that move along other surfaces (metal to metal, metal to plastic, etc). Think of all that black gunk you see as inefficiencies you are removing from your pistol.

Now that everything is cleaned up, you will need to lubricate the system. As always, only use 100% silicone oil for this process. LIGHTLY oil any rubber surface or ones that come in contact with any moving component. Use one drop and smear it across the surface. I will tell you this already, YOU ARE USING TOO MUCH OIL. A light coat is more than enough, too much will actually attract dirt and gunk up the system faster. Okay, so now grab the slide and pull the Nozzle forward, exposing the rubber seal. They come in many shapes and colors, but on G&G Pistols they are green. Put two drops directly on the seal and cycle the nozzle to spread the oil. When this is complete, reassemble the pistol, wipe down the surfaces, and you are done!

Additional Maintenance Notes: All the greats will say, after a day of play, be sure to empty your mags of all BBs and gas. This will preserve the seals and springs on your mags. With the empty magazines, fill each with a little gas in each to keep pressure on the seals. Do not store filled magazines as gas can expand with heat from the sun or hot weather. This will cause valve failure and damage to any surroundings.

Conclusion

You are now ready to take to the field! Take your knowledge and educate the masses. At the end of the day it comes down to comfort and feel. Get used to your current system and see what changes would best suit your playstyle. The joy of this sport is the options you are presented with. No one path is best for everyone.