Nerf/blowgun Airsoft Gun

This is a quick and easy way to make a bb shooting device.
I know this isn't very powerul but I made for my little cousin.
Feel free to make suggestions.

1 nerf dart tag pistol
1 dart
pliers
knife(doesnt matter what kind)
Bic round stic pen

To make the barrel cut the top of the dart off and remove the insides of the pen so you can see through bothe of them.Then, place the pen inside the dart.

To fire this like a gun put the dart end of your barrel in your gun,cock it, place a bb in the barrel and fire.
To shoot like blow gun, put a bb in the dart end of the barrel, and through that end.
You can also put the barrel in any other gun it will fit in.