Shotguns have a very short range of fire, similar to Elemental Weapons. They are also inaccurate, making them close-combat weapons. However, shotguns have very high impact and fire more projectiles at once, which makes up for their bad accuracy. It is hard to miss with a shotgun, due to their wide spread of fire. Shotguns usually have a medium fire rate. USAS12 is an exception, which has a fire rate similar to a Rifle.
If you can't control Elementals, use Shotguns. They can also be used by Ninjas as offensive weapons, to make surprise attacks.