My son and I want to make a potato cannon from plans in the Backyard Ballistics book (check Square One). We are having no luck finding the right kind of pipe. Most hardware stores only carry PVC pipe and fittings up to 2".
We need:
14 inch length 3" SCH40 PVC pipe
3 to 2 inch diameter reducing bushing
3" coupling, one side smooth, one side threaded
3" threaded PVC end cap.
We have/can get all the other items we need. Anybody (plumbers?) know where I can secure these items to begin construction?
Thanks in advance!





















































































