Hello! Today we will talk about how the GBB pistol works, what the temperature and gas pressure affect, and why you should not fill Tokyo Marui pistols with black Guarder.
Everything in this article applies to GBB guns powered by green gas. Many points, of course, are also relevant for CO2 pistols, but they have their characteristics.
Let’s start with gas. The gas in the filling cylinder and the pistol magazine is contained in two fractions at once: gaseous and liquid.
This is necessary to pump some sane amount of gas into a cylinder or store.
Let’s explain. If the gas were only in the gaseous fraction, then it would be enough for a couple of shots, since the amount of gas substance per unit volume of the gaseous phase is extremely small compared to the liquid one.
That is why the gaseous phase is compressed under high pressure, turned into a liquid, and pumped into the tank.
A logical conclusion follows from this – the GBB pistol must be refueled while holding the cylinder from above OVER the magazine so that the liquid gas fraction overflows into the magazine.
Liquefied gas has such a characteristic as saturated vapor pressure. It is different for each gas and is determined by the properties of the substance.
We need to know that the vapor pressure of a gas depends on temperature.
The effect of temperature on gas in airsoft guns
- The warmer, the more pressure.
- The colder, the less.
When the temperature drops below the boiling point, the gaseous fraction completely turns into liquid and the pressure becomes zero.
This means that at -42°C or less, your GBB gun will not work at all.
However, at this temperature, this will be the least of your problems.
Let’s say you’re trying to shoot not at -42 degrees, but let’s say under normal conditions with a room temperature of +20°C.
You fire a shot and part of the gaseous fraction passes from the magazine into the gas chamber of the pistol.
At this point, reduced pressure is formed in the store and the boiling point of the gas shifts.
And since the boiling point depends on pressure, the liquid fraction begins to boil and evaporate. The pressure rises, the boiling point shifts back to the starting point and equilibrium occurs.
And so every time after the shot.
Influence of the area and volume of the container on gas
Another important point! The rate at which pressure is restored directly depends on the area with which the gas evaporates.
The larger the area, the faster the pressure builds up. To make it clear, a boiling pot will make more steam per unit of time than, for example, a boiling glass.
Now compare the surface area in a single-row narrow magazine for the Colt 1911, in a wide magazine for the Hi-Capa, and directly in the tank, on which the adapter hose is wound.
Now you know why any GBB Colt 1911 with a narrow magazine does not perform well in tempo fire and why the Hi-Capa holds the exhaust so consistently.
And also why any gun connected through a hose directly to a green gas cylinder keeps the exhaust stability even better.
And the volume occupied by the gaseous fraction is also important.
The larger it is, the less the total pressure in the store drops when some part of the gas is lost when fired. And the faster it recovers.
And finally, an important and inexorable point is the cooling of the surface in the process of transition of a substance between aggregate states.
When on a hot day you come out wet from the water into the air and if you do not immediately dry yourself with a towel, then you get cold very quickly.
These are drops of water evaporating from the skin, taking away part of the heat from it. The hotter it is, the faster they evaporate, and the colder you are.
The same thing happens in the gun store. When the liquid fraction of gas evaporates, it cools and cools everything around it. Including the store building.
That is why, after shooting at a high pace, the store is cold. And as we already know, the lower the temperature, the lower the pressure, and it recovers more slowly.
From this, we can draw a sad conclusion.
Despite all the marketing tricks, the GBB airsoft gun and assault rifle will NEVER give the same exhaust stability at tempo fire as the AEG or VVD.
Now that you know why Tokyo Marui’s HI-CAPA is the best GBB pistol ever, let’s get straight to how pistols work.
The principle of operation of the pistol on green gas
What happens when you pull the trigger on a GBB pistol?
Let’s figure it out.
When you pull the trigger, the trigger hits the outlet valve stem in the magazine.
The stem moves to open a hole in the sealed tank.
The pressurized gas rushes through this hole to freedom and, in its rush, flies past the rubber ring.
This ring is put on the valve and in the closed position is compressed between this very valve and the magazine body, preventing the gas from escaping.
Remember this ring.
Next, the gas flies out of the magazine into the cylinder of the pistol’s gas engine.
So that the gas does not scatter in all directions along the road, the magazine fits snugly against the gas cylinder with a rubber part.
Remember this detail too.
So, the gas got into the gas engine and then rushes through the nose into the hop-up chamber and starts pushing the ball, the ball accelerates along the barrel, flies out of the barrel, and the gas flies out behind it.
The pressure has dropped, there will be no blowback… Not really.
To prevent the above from happening, another valve is installed inside the node, the so-called rocket valve.
When the gas pressure in the nose reaches a certain value, it overcomes the rocket valve’s spring force, the valve moves and closes the hole in the nose, separating the barrel from the gas cylinder.
The most interesting thing is that the portion of gas that will fly away with the ball is much less than the one that remains in the cylinder.
This explains why guns without a blowback are many times more economical than with a blowback.
And yes, the rocket valve also has a rubber ring.
The remaining gas continues to push in all directions. The path to the barrel is closed to him, the strength of this very cylinder prevents the cylinder body from breaking.
He is prevented from going back to the store by the gas pressure in the store and the strength of the bypass rubber gasket.
Therefore, the gas does the only thing left for it – it presses on the piston.
Which is SUDDENLY inside the gas cylinder on the other side of the nose and rocket valve.
And which is rigidly connected to the gun slide. And it also has a rubber seal! Ring or cuff, it doesn’t matter. What matters is that it exists.
Under gas pressure, the piston and the entire slide begin to move backward, the cylinder remains in place maintaining pressure and, most importantly, increasing its internal volume.
The larger the volume, the lower the pressure.
Therefore, having reached the rearmost point in the cylinder, the maximum volume is formed, the gas pressure drops below a certain value – the rocket valve opens again.
The body of the cylinder with the nose, under the action of a return spring, flies to the piston, and the already unnecessary gas whistles to freedom through the extraction window of the sleeve in the slide.
After that, the slide with all the contents returns to the front, grabbing a new ball from the store and sending it to the hop-up.
On the rollback, the slide squeezes the activator and the trigger mechanism disconnector, and also cocks the trigger spring, retracting it to the rearmost position.
It is at this moment that the outlet valve in the magazine closes and the gas supply to the gun stops.
The cocking of the hammer pulls back the striker, allowing the valve stem in the magazine to return to its original, closed position.
And the disconnector squeezed before this separates the trigger pull and the trigger, preventing the latter from breaking forward when the trigger is already pressed.
Now the gun is ready for the next shot, and you know how the GBB gun engine works. If you look, then it is many times simpler than any AEG’a.
Why are AEGs generally more reliable and durable?
Yes, because there are many times more places in gas pistols, the breakdown of which breaks the entire system.
And now we recall all the rubber rings and seals that we asked you to remember.
Many of these rubber bands are also mobile and subject to constant friction and a sharp pressure drop.
And there are also a bunch of springs, the correct calculation of the effort of which determines when this or that part starts to move and what volume of gas will be involved in the work.
In AEG, there are ONLY THREE rubber seals in the gearbox, only one of them is movable under load.
There are two springs in the pneumatic system. And the energy for work is provided in general by the electrical system. Therefore, there are several times fewer points of failure and that is why AEG is more reliable.
Now that you know what the gas does in a GBB system, let’s talk about pressure. And here, in fact, everything is very simple. The higher the pressure, the stronger the kick the ball and gas piston get.
In the case of a ball, this is not very critical. With more pressure, the rocket valve will simply close faster, cut off a smaller portion of gas, and the increase in the exhaust will not be very large.
But in the case of the blowback mechanism, the pressure from it will not go anywhere until the end of the working cycle.
Unless, of course, strongly excessive pressure breaks the seals and the gas does not escape into the atmosphere.
Therefore, with more pressure, the blowback mechanism and the body of the gun will get a stronger kick.
In a bad case, this can result in faster wear and, as a result, breakage of parts. For normal operation here again a balance is needed.
Just think about it. By increasing the pressure, you slightly increase the exhaust of the gun, but significantly increase the load on the blowback mechanism and body.
That is, the pressure should not be excessive, but such that it is enough for the normal operation of the blowback. And for each gun, there is some specific optimal pressure.
You need all this information so that you understand how it all works and why in some cases the GBB gun works well, and in others, it does not.
Types of green gases
Firstly, because they have several types of gases, and secondly, because the manufacturer adjusted several samples for us and, in general, because this is an advertising integration =)
There are 4 types of gases in the FL gas range:
- “Regular” green gas with normal silicone lubricant content;
- “Conservation” gas with a high content of silicone;
- The so-called gas for IPCS, where this lubricant is at a minimum;
- And gas for Tokyo Marui pistols.
“Regular” green gas
“Regular” green gas consists of high-purity propane and some silicone grease.
The manufacturer’s website claims a pressure of 0.8 MPa, which corresponds to approximately 120 PSI at an ambient temperature of 20 degrees Celsius.
Silicone lubricant in the composition of the gas is needed not so that it slips better through the gas system, but to protect all rubber seals from destruction. You remember that the GBB pistol has a lot of rubber rings, gaskets, etc.
So know that under the influence of air oxygen, rubber gradually collapses, and cracks and deformations appear in the integral structure of the part.
As a result, the part loses some of its strength or is destroyed. And the pressure of the gas, instead of activating the mechanisms of the gun, whistles in different directions.
To protect the rubber from destruction, it must be covered with a protective film. This is what the silicone grease in the gas composition does, settling on the rubber seals with each shot.
FL regular green gas fits most GBB metal slide pistols. It has an average pressure, which is sufficient for the reliable operation of automation under normal conditions.
Gas for IPCS
The FL IPSC, as the name implies, is for those who shoot Action Air IPCS. It has a reduced content of silicone lubricant, and in fact, it is almost completely “dry” propane. The pressure is the same, 120 PSI at +20.
Why is IPCS less lubricated? It’s very simple – they shot many times more than ordinary airsoft players. Several thousand shots in a training week are normal. An ordinary airsoft player may not shoot so much in a year.
And if you use ordinary green gas with such a large volume of gas that is driven through the gun in such a short time, the silicone grease in the gun remains mama don’t worry.
Including hop-up elastic. And we all know that a hop gum needs to be dry to function properly. Therefore, the lubricant content of the IPCS gas is reduced.
As for all other rubber bands, professional shooters tend to MAINTAIN their guns, unlike airsoft players.
And after training, disassembling, cleaning, lubricating the gun, and driving a couple of magazines of ordinary gas through it to lubricate all the seals is normal.
Now honestly tell yourself – how long have you serviced your GBB gun?
Conservation gas FL
Conservation gas, on the contrary, contains an increased amount of silicone grease. This is necessary to create a thick layer of silicone on all the rubber bands in the gun, for example, for storage. So that after six months of lying in the closet, your gun still shoots normally, and does not spit outgas in different directions.
The second function of this gas repair. If some rubber seals already have microcracks, then filling them with a bunch of silicone can repair these cracks and partially restore the integrity of the part. And the store, which used poison gas, will stop the poisoning.
BUT! This is a temporary crutch and a minimally costly way to make the gun work RIGHT NOW. Because by filling the cracks with silicone, you still cannot restore the original integrity and strength of the rubber part.
And the part will continue to gradually collapse, but just more slowly. Therefore, the final solution can only be the replacement of the entire part with a new whole.
Tokyo Marui pistol gas
And finally gas for Tokyo Marui pistols.
But this is no longer propane, but a technical freon brand HFC134a. It has a lower vapor pressure than propane – the manufacturer indicates 0.6 MPa, which corresponds to 87 PSI at + 20 ° C.
At first glance, this seems small. Yes, Marui seems to work fine on regular green gas and even sometimes survives on the “black Guarder”. However, not all so simple.
As you know from the part about how the gas works in the GBB gun engine – most of the energy in the gas goes into pushing the slide back. The more the gas pushed the slide, the stronger the blow with which it flies into the pistol frame.
Another point – the more the slide weighs, the more energy is needed to move it from its place, overcome the elasticity of the return spring and bring the recharge cycle to the end.
Tokyo Marui pistols have a plastic slide and are very light. To move it from its place and ensure reliable operation of automation, less energy is required than in the case of a metal slide of some WE, which is noticeably heavier.
And since Japanese engineers are Engineers with a capital letter, they calculated the entire operation of the gas engine under a small gas pressure, which is enough for the reliable operation of automation and at the same time does not create excessive slide impact energy.
Accordingly, the nominal pressure of 120 PSI on regular gas is about a third more than planned by Tokyo Marui engineers. Accordingly, when using conventional gas, the gun operates in overload mode.
Some models from Tokyo Marui, especially the new ones, cope with this overload, and some have cracked slides and parts fly.
If you want to avoid risk, then just the same, you can use this special gas for Tokyo Marui pistols. Again, depending on the ambient temperature of use. Where it’s warm and hot – gas for TM. Where the temperature is only +10, then you can take ordinary or IPCS gas. This will allow it to be used in pistols with a metal slide.
You can also use this gas with regular pistols if you are playing in the heat. Those who play in hot climates and without us know that on ordinary propane at +35, the drummer may not break through the valve at all due to excessive pressure in the store.
And that’s all we have for today! We think that you have already received a lot of information on the topic and now you will be more conscious in choosing a pistol and choosing a gas for it.