yes, I did not invent this... but, I modified it so it is simpler for you out there to make it
I AM NOT RESPONSIBLE FOR WHAT YOU DO WITH THE SHOOTER
Step 1: Things You Need:
2) Tape (any kind)
Step 2: Preparations
Then cut out your marks with the Razor knife, but only one should have the jack
Step 3: More Preparations
Step 4: Creating the Barrel
Step 5: Get It Together!
Step 6: Adding the Spring
Step 7: Fire!
Pusth the flat end into the barrel, until the spring snaps into the notch.