Power: Typically measured in distance or PSI, a water gun’s power will play an enormous role in its overall performance and user experience. Not only is this area responsible for how far a water gun can shoot, but it will also play a massive role in determining a given model’s accuracy — especially from a distance. Size: As previously mentioned, modern water guns come in a huge variety of shapes and sizes, with the larger options on the market almost always boasting more power and range — albeit at the cost of portability and child-friendliness. Ammo” Capacity: Though it limits portability, the volume or reservoir of a water gun will directly determine how much “ammo” it can store — a metric that will directly determine how long of a firefight one can enjoy before having to refill their weapon.