Gbb Airsoft How Do I Put Green Gas Into My Bell M9 Airsoft GBB Pistol?

How do I put green gas into my Bell M9 Airsoft GBB pistol? - gbb airsoft

How long should I insert the tube is filled to the magazine?

Any advice for people who never blwoback gas?

The 707 is a model of the Bell M9 Beretta EC