This is the coolest dart/nail gun EVER!!! The gun is originally a NERF TITAN ASV-1,
(Missile Launcher). I had it as a airsoft gun before but I made it better. This is my first ever instructable so please take it easy and feel free to give me suggestions on what to do better.
Thank you.

Step 1: Materials

Materials:
     Tape- lots
     Nail(s)- for more than one dart
     Index cards
     TITAN ASV-1 (NERF)
     Longshot extension gun
     scissors or x-acto knife (I prefer both)
     cardboard
     pen tubes

Step 2: Outer Barrel

Take the barrel out of the longshot extension gun. You dont need the tape at the end like I have it.

Step 3: Inner Barrel

Take everything out of the pens, you only need two.
Tape them together so they don't move a lot.
Also put a fat marker tube around the end.

Step 4: The Gun

Take the big barrel off and cut out the plastic so the inner barrel fits tightly in it.

Step 5: The Dart

Make a cone out of the index card, then push the nail through the hole at the end of the cone.
Tape the nail and cone together to look like the image shown.

Step 6: Using the Nail-Dart Launcher

First, put the inner barrel in, then pump the gun (min. 10pump-max. 30pump).
Put the dart in the bottom of the outer barrel, then place the outer barrel around the inner barrel
and push it in the little slot on the end of the gun. FIRE!!! When pumped thirty times it goes through like in the picture. Enjoy.

/!\ NEVER EVER EVER FOREVER NEVER POINT THIS AT SOMEONE OR LIVING THING THIS CAN INJURE OR KILL SOMEONE!!! I AM NOT RESPONSIBLE FOR ANY ACTION YOU MAKE!!!!/!\