Hello this is my first post on deviant art.

I'm a fan of FMA,inuyahsa and stargate atlantis. Anyway I was watching this show called MacGyver because it was going to be on Mythbusters and I got a really cool idea to make a crossbow that shoots pens or pencils out of:

clickie pen springs
rubber bands
paperclips
and those tumbtacs like things that you can easily pull or push out of something (I think they're called push pins but i'm not sure)

but i don't know how to make it work

I need help from someone with an analytical brain. Also known as a macgyver brain. If your not familiar with the show it is simply someone who is able to make complicated machines out of ordinary things.

I take any help i can get . preferably with instructions or a diagram

Thanks in advance

Timelord53