Hop-Up Chinese is called the top spin. In the gas dog, it means that the airsoft BB will have an upward rotation. The airsoft BB will rub against the air when it flies forward. The air will slide around the airsoft BB. If the airsoft BB is rotating upwards, the air will pass through the upper part of the airsoft BB and cause a lower friction force due to its direction of rotation. On the contrary, the air passing through the bottom of the airsoft BB is opposite to the direction of rotation, thus making a large friction force. At this time, the following air friction force is greater than the above, it will produce a slight buoyancy. 

Although this buoyancy is very small, for the airsoft BB with only 0.2g weight, it can greatly slow down the speed of the descent and fly farther, while the rotating The faster the speed, the greater the difference between the upper and lower frictional forces, and the greater the buoyancy, but the excessive buoyancy will make the airsoft BB "floating" upwards during the flight, which is not good. So if the dog's Hop-Up can be adjusted, it should be adjusted to airsoft BB almost straight forward is ideal!! (The weight of airsoft BB will also affect the effect of the spin, the heavier the less, but the heavier airsoft BB The launch distance will definitely be much shorter.)

What is BLOW BACK?

Blow Back- is a retracting action. It is a kind of operation procedure when the curved dog is launched. The principle is that when the bullet is fired, the explosive force is pushed backwards. The function is to release the remaining shell. When the bounce is exhausted and the explosive force is exhausted, the carriage will be pushed back by the return spring, and this action will push the next particle in the magazine into the shit to prepare for launch, and so on. In order to increase the degree of simulation and the fun of playing, new gas products are designed to have this action. Just like a real ruler, you can retreat to launch the next particle bomb. And this type of hand dog has the words "Blow-Back"!!