Shotguns have very short range of fire, similar to Elemental Weapons. They are also inaccurate, but they have very high impact. However, shotguns fire more projectiles at once which makes up for their bad accuracy. You can't miss with shotguns. Shotguns usually have medium fire rate. USAS12 is an exception, it has fire rate similar to a Rifle.
If you can't control Elementals, use Shotguns. They can also be used by the Ninja as offensive weapons, to make surprise attacks.