This is a hunting blowgun made from stuff laying around the shop. I shot two rabbits from about 75 to 100 feet with this. Depending on the materials you use for the darts, you can shoot it up to 150 to 200 feet easily.
Step 1: MATERIALS LIST
3 to 6 foot piece of 1/2" electrical conduit. forget about 1/2" PVC. I tried it and the conduit works a lot better. The longer the pipe the more speed an accuracy you get BUT, it also takes more air and its harder to carry around. Try 4 feet to start with.
A cone shaped paper drinking cup.
Either 16 to 20D nails or 2 1/2 to 3 inch dry wall screws. If you use the nails, sharpen them on a grinder. Go slow so you don't burn the tip. If you don't have a grinder use the dry wall screws, they don't need to be sharpened. Not as much distance or knock down power but it will still kill a squirrel or bird.
A razor blade or razor knife
Step 2: Making the Dart 1
Push the dry wall screw or nail through the cup from the inside
Step 3: Making the Dart 2
Put the nail into the pipe
Step 4: Making the Dart 3
Cut off any of the cup that sticks above the end of the pipe
Step 5: SHOOT IT
Push the dart about 1/4 inch down the pipe, aim by looking down the pipe and put the other end of the pipe where you want to hit about 20 feet away and blow hard and steady until the dart has left the pipe. Longer distances will need to raise the aim a little bit. 30 minutes of practice is enough to give you some really accurate shots. now go get your dinner but remember, Don't kill anything you don't plan to eat and don't shoot any living thing you aren't planning on killing .... INCLUDING PEOPLE.