My 10-year old son is really into Star Wars so I made him a "blaster" out of pvc pipe and he LOVES it. I also made one for a neighbor's son (also age 10 also into Star Wars) and he loves the blaster.
I purchased the 1/2 inch pipe and fittings from my local Home Depot. Cut the pipe with a hand held pipe cutting tool (looks like scissors).
Decorate with duct tape.
Click on the link below to download a PDF showing all the dimensions and fittings I used.