Hey guys, this is my first instructable! Make sure you read the whole thing before building because i backtrack a bit. Comment on improvements or flaws and enjoy. Check out my airsoft grenade instructable at https://www.instructables.com/id/Airsoft_Grenade_5/
A Fully Automatic Gun that can shoot 6mm BB's. I actually haven't done this yet, but it should work. IF it does.... I AM NOT RESPONSIBLE FOR ANY ACCIDENTS OR INJURIES THAT MAY OCCUR WHEN USING THIS GUN, AND I STRONGLY RECOMMEND THAT YOU DO NOT MAKE THIS GUN.
Step 1: Materials
The gun consists of a wooden frame, a 9v battery, a 9v motor, a 7mm tube that won't bend easily (I'm going to choose aluminum), a wooden trigger, wire, a small wheel, a wooden clip, electrical tape, 6mm BB's, a drill with a 7mm bit, some hinges, a spring, and some aluminum foil.
Step 2: The Insides
Here's a diagram of roughly what the gun should look like. You don't have to have two handles. I forgot to add a door for the batteries to be switched out, which would make life easier.
Step 3: Frame
Take a piece of wood and carve it into a gun shape. Make it wide so that the components can fit inside. Then take a 7mm drill and drill through the spot where you will shoot, almost all the way to the other side of the block. Once you do that, cut it in half so that there are two symmetrical gun shaped pieces. After that, take each piece and cut some of the bulk off of the inside while keeping the edges the way they are (it's hard to describe, so look at the picture).
Step 4: Battery Hole!
Cut a hole a bit bigger than a 9v battery into the handle of the gun and keep the piece of wood. Take a hinge and attach it to the gun and the piece of wood so that it swings open and closed (don't worry about it swinging open, you'll be holding it down when wielding the gun.
Step 5: Motor!
Attach two wires on either side of the motor and attach the motor to the gun. I just realized you shouldn't gut out the whole block of wood, you should leave a "shelf" for the motor to be attached (leave two holes for the wires). hot glue the motor to that shelf and put the two nubs for the wires to attach to into the holes. Attach the wheel to the motor and test it out. once that is done, attach the one of the wires to one end of the 9v battery. the other should get a piece of aluminum foil on it that gets taped down. make the foil stick up so that the other piece of foil (mentioned in the next step) can come into contact with it when the trigger is pulled.
Step 6: Trigger
Make a trigger out of wood, it doesn't have to be much, just a block or a block with a curve to it. attach a hinge to the part of the gun it will hang off of to it. then attach the spring to the wall that the trigger moves towards and to the trigger. !!!! just realized that there should be a hole on the gun where the trigger's bottom would touch. then glue a wire to the bottom of the trigger and stick the wire through the hole. attach a piece of aluminum foil to the tip of the wire. add another wire that branches off of the first one and attach that to the end of the 9v battery.
Step 7: Getting There!
Now, rest the tube on one of the half hole things, glue up the edges, and put the other one on top. You have your completed gun! now you just need the clip.
Step 8: The Clip
this is pretty easy. Take a block of wood, cut a hole for the BB's, cut it in half, gut it (like before) and hot glue it together (you can make it with something other than wood if you'd like). if you followed the diagrams correctly, you should now have everything you need for your gun to work!
Step 9: WAAAAAAAAAAAAAAARRRRRRRR!!!!
Go out and have some fun!
Step 10: In Action
Once i build mine, i'll show you how it works.