Shotguns are a special type of class in airsoft weaponry. They all take the appearance of real life shotguns but not all of them will function the same or be powered by the same mechanism. The ones we offer here at Fox do function similar to how a real shotgun will fire. Depending on the brand and model you get, these shotguns can fire 3 shots at once or more. They will typically feed from a magazine which is designed to look like a shotshell and these hold 30 rounds. If you fire them from a shotgun that fires 3 rounds at once, you're going to get 10 shots out of that magazine.
Shotguns are available at different price levels and realism levels. The lowest priced options for shotguns would be spring powered shotguns. These are like big versions of the manually cocked spring pistols that you see except these will fire the 3 shots per trigger pull as mentioned. These are inexpensive to get into because you do not have to spend on any fuel or propellant and all you need is ammo and arm strength to prepare it to fire.
Gas shotguns are different in that they are easier to manipulate. When you pull back the pump you are not pulling on a big spring which means it is much easier to pull. Gas shotguns fire a minimum of 3 shots as well and some models may have an option to shoot more. But being gas powered this means it will cost more to operate and green gas is particularly fickle during the winter months in places where temperatures get too cold for it to function efficiently. However nothing beats the weight and feel of a nice metal gas shotgun and the sound it makes when you pump it.
Spring and gas shotguns don't shoot as hard as sportline AEGs in our observation making these types of guns very popular for CQB/indoor airsoft fields. Obviously a pump action type gun is slower to shoot than a SMG or rifle or pistol but many people pick shotguns just to have fun. The range on these shotguns will be pretty short but they still remain very effective at CQB.
Spring shotguns are self contained by design and cannot be upgraded but also require pretty much no maintenance. Being of simple design but sealed does keep their price down but it makes it not feasible or often not possible to repair. But because of that, if you do not pump the shotgun positively and try to pump again you run the risk of double feeding the shotgun and causing a jam.
If you should decide to go into gas shotguns, you should know that gas shotguns just like any other gas airsoft gun requires regular maintenance. You will want to keep the internal seals lubricated by adding silicone oil while filling green gas. The pressure from the gas will disperse the oil into the insides of the gas shotgun where needed. You do not want to take apart any gas shotguns for maintenance as it is not needed.