Gun fires but no BBs come out.

a, Check to see if the magazine is fully loaded.
b, Check to see if the magazine is fully wound.
c, Check to see if the magazine is fully seated into the receiver. It should click when fully seated.
d, Remove the magazine and check if the magazine is jammed or gun barrel is jammed.

BB jams in barrel.

a, Remove the magazine, use the bevelled end of the cleaning rod to push the jammed BB back of the BB loading nozzle. (See Clearing a BB Jam)
b, Dry fire with no BBs to make sure gun is firing properly. Reinsert loaded magazine and test fire.
c, Use only new, high quality BBs of 0.20g weight or heavier. Do not use 0.12g BBs.

Motor is heard whining, but gun does not fire.

a, Adjust the motor height by using an appropriate wrench on the screw on the bottom of the pistol grip. Tighten screw until the gun fires smoothly.

Motor is heard grinding and the gun fires slowly.

a, Adjust the motor height by backing out the grip screw until the gun fires smoothly.

Gun clicks when the trigger is pulled.

a, Charge your battery and try again.
b, Try another fully charged battery.
c, Check to see if your motor grip screw is too far in.

BBs do not fly straight.

a, Adjust hop-up as detailed in the product manual.

BBs do not fly very far.

a, Clean your inner barrel and add a minimal of silicone lubricant into the BB loading nozzle. (See Cleaning the Inner Barrel)

Motor grip is getting hot.

a, This can be common and a little heat with heavy usage can happen, but is best to disconnect the battery and set the gun down for a minutes to be on the safe side.

Battery is smoking.

a, Immediately stop shooting.
b, Disconnect the battery and set it in a non-flammable area if possible.
c, Consult with your battery instructions or an authorized airsoft gunsmith.

Charging the battery.

Most quality airsoft guns do not include a battery and may need to be acquired separately. When you receive a battery it will be empty or almost empty. Using the gun with a drained battery can cause damage to its spring, gear or motor. You should always charge your battery completely before you use your item especially when it is the first time. If the gun's rate of fire and trigger response decreases you know it's time to stop and recharge the battery. And again avoid using the airsoft gun with a low battery as it can leave the AEG with a jam or compressed spring (See Compressed Spring)
For Lipo batteries please be extra careful as there are extra risks for these batteries. Have a safe place to charge then with nothing flammable around them. Be aware of generally how long it should take to charge and wait for them. Eg: don't fall asleep or leave your home while charging lipo's. If a Lipo battery goes puffy a chemical reaction has begun and can't be revised, please remove it to be disposed in an appropriate safe battery disposal.

Setting the Hop-up.

A common mistake a new Airsoft can make is forgetting to set the hop-up or to make matters worse, turn it up to full. It puts spin on the BB helping it control the trajectory. The BB drops quickly in case of a little hop-up. Too much hop-up the BB will arc up and could even jam a bb in the hop unit. To have a nice flat trajectory the Hop-up mechanism is used and adjusted in small increments to find the right hop position. It is best advised that you follow the manufacturer's guide or experienced airsofter for best education on this matter.

General Cleaning.

It is advised that you don't use water to wash the gun, due to potential rust and electrical issues, or if you do a damp cloth at a minimal. Best option you can use a silicon lubricant to wash it and help prevent rust. For finer detail use Q-tips, and get all the small little cracks and crevices. If its metal you're cleaning you might want to spray some silicone oil on it and rub it off with paper towel really good. Silicone Oil is a good way to prevent rust from appearing or spreading. Although don't use too much lube or your gun will become a dust magnet. So again a gentle rub down with a silicone dampen cloth is best.

Cleaning the Inner Barrel.

As airsoft internals systems are completely different from real steel systems, so is the inner barrel cleaning is required a lot less then for real guns. Dust and dirt can still build up if it's not removed and cleaned every 6 months so from a regular used airsoft gun.
To clean the barrel properly, take a cleaning rod, with a small tissue patch and spray small amounts of silicone spray to the patch. Turn your hop up completely off before you insert the cleaning rod.
Inside of the barrel needs to be wiped down in a back and forth motion. Remove the tissue patch from your cleaning rod. Use a new, dry patch inside the barrel.
You may have to repeat the process to clear out the remaining residue until the tissue comes out near clean from dirt from inside the barrel.

Clearing a BB Jam

NEVER look down the end of barrel for any reason!
1. Make sure the airsoft gun is "ON SAFE" and pointed in a SAFE DIRECTION.
2. Remove magazine.
3. Insert the tapered end of the cleaning rod into the barrel, with the angle toward the magazine connects to the Hop-up
4. CAREFULLY and slowly apply more pressure until you push the BB out of the breech.
Reinstall the magazine and test gun.

Semi only Jam.

A problem that new users may face is sometime shooting in semi only the gearbox gets stuck. This problem is very easy to correct by just putting your gun to auto and fire a few rounds to free up the gearbox, and then switch back to semi if required. Can also occur with a low battery, and a fully charge battery with a full auto burst will correct this.

Compressed Spring.

A compressed spring can occur naturally in the normally full auto cycle of an AEG and happens when the piston is positioned fully at the rear of the gearbox. This in itself is not an issue.
But a problem of compressed spring that can cause damage / power loss, once it's in this position and the model is put in storage for a long period of time.
The simple solution to this problem is every time before you pack you gun away is to fire the model in single fire mode first and this will release any compressed spring.
If you model has suffered from a compressed spring once removed from storage, the spring will need to be replaced to regain the lost power.

AEG Storage.

Always remove batteries from AEG and discharge them (non-Lipo) for long storage.
All hopup's should be turned off and BB's removed from mag to decompress springs.
A little silicone oil spray on moving parts and rubbers before and after storage can also help too.

General GBB Maintenance.

With regular usage or removing from storage, it is important to remove the slide to spray the slide grooves and around the loading nozzle in the rear of the slide with silicon oil. The loading nozzle should be able to spring forwards and backwards with ease. A barrel clean every 5000 rounds can marginally help with accuracy.
Also note: GBB pistols do not perform well under 10°C. You will experience gas rushing out of the barrel, reduced power and cycling problems. Optimum performance is achieved in temperatures of 18°C and above.
DO NOT use any petroleum based lubricant like WD-40 as this corrodes any plastic or rubber inside the pistol.

GBB Mag Loading.

To load a GBB mag with gas, the bottle is held at a 45 degree angle above the mag infill valve and pushed together. Some gas may escape, but this is not a problem.
If you try this horizontally / sideways, the mag won't load with gas properly and only be half filled at best.
For a M1911-sized magazine, approximately 5-6 seconds fills the magazine. For larger Beretta/Glock/Sig magazines, 6-10 seconds fills the magazine fully.
Input bb's into the mag as per instructions in the owner's manual.
To insert the mag in the airsoft gun, lock the slide to the rear (empty position) before inserting the mag. Release the slide and you're ready to shoot.

Leaking Gas Mags.

Gas mags leaking is inevitable. What matters is you know how to maintain them well so the leak less or never if well maintained. Always keep your o-rings damp with silicone oil spray and keep valves tightened if they become loose. DO NOT drop your GBB mags, no matter how cool you think it is! They are not designed to be dropped!
If gas mags are dropped to many times, the structure can become damaged and can even explode.
The design of most mags are simple, in-valve, out-valve, and o-rings between two halves of a body, with spring and pusher for bb's.
So sealing issues can be simply aided with silicone oil and more with Teflon tape or even thread lock glue in the metal on metal areas if need be. But please make sure all gas is removed from the gas mag before any form of maintenance or opening of the mags is attempted, as they can explode if you try.
To release the gas press the knocker valve (outward valve) on the back of the magazine to expel gas from the top of the magazine, but point the vent in a safe direction first.

GBB Mag Storage.

Never leave your Gas magazines filled with gas in storage.
The full pressure will deform the o-rings releasing the gas and o-rings will need to be replaced.
But it is recommended just a bear minimal of gas in you mags is to keep a good seal in storage. And a little squirt of silicone oil on valves won't hurt ether.