Spin up or Hop up is when a bb is shot from an airsoft gun, there is a friction placed on the upper side of the bb while exiting the barrel. This friction causes the bb to "spin upward" or a backwards / under spin. This mechanism is called the Hop-Up. The Hop-Up configuration determines the range of bbs or extend the effective range of an airsoft rifle. Most spring airsoft guns come equipped with "built-in" Hop Up which is not adjustable nor calibrated. However, higher end models, such as gas airsoft pistols and electric airsoft rifles can be adjusted or calibrated both to the type of BB being used and the flight path desired. The below diagram illustrates the effects of hopup and how to callibrate your airsoft gun correctly. Towards the bottom of diagram it coveres the bernoulli's principle and it's effect on the path of a BB with hopup.
An Airsoft gun
A pump airsoft gun is a gun that has to be pumped every time before shooting. Ex. Airsoft shotgun
No
No
It is an airsoft gun based of the PPSH-41 gun
You never need a license to have an Airsoft gun.
Yes this gun has great accuracy if you adjust it and set hop up right
No
No, it is an airsoft gun.
NO
If you use airsoft gun in public place or pretend it's a real gun - yes, you can be shoot. Do not use airsoft guns in public places!
It stands for Airsoft Gun Manafacturer.