This is a Lego device that when the wheel is turned it will fire four darts one after another.
Step 1: Parts Needed
Here are all the parts you will need. You will also need a base plate of some kind.
Step 2: Bulding the Base
This it the basic structure, just follow the pictures.
Step 3: The Main Gun
Like the title says, this is the construction of the main gun.
Step 4: Random Bits
This is really the parts for the auto firing system.
Step 5: Putting it together
Here you will be putting the pieces you have made so far together.
Step 6: Adding the Turning Mechanism
This is the last part of the gun! It is so that firing it will be much easier.
Step 7: And You're Done!
Congratulations! You can now make a case for it or what every you want! Also to fire just load each cannon and turn the knob counter clockwise.