Carbon Fiber?
a much less expensive way to add reinforcement to a pvc cannon is to wrap it with fiberglass. as pete zaria said, carbon fiber is in its infant stages of industrial usage. that along with new superalloyed metals and exotic composite materials are still consumer science fiction. but the military uses these every day. just wait about another 20 yrs and we'll be launching spuds into orbit with chambers and valves capable of handling thousands of pounds of air pressure.
