Is it just me or does treating a PVC pipe as a serious threat sound just a little like over-reaction to anybody else?
The burst strength of pvc is such that you woule never build up a gas pressure sufficient to accelerate much of anything, certainly not the pipe itself.
I'm not an expert, but I think it would depend on what you were using as explosive material inside the pipe itself. From what I've learned over the last few weeks in research associated with OU, even small amounts of some explosive material (probably not the stuff typically found in the case of a pipe bomb) can be very dangerous...