thats kinda a good point. lol, but seriously, why would you need a distance of 100 meters if you yourself were talking about how you would stop this contraption.
Also, a pvc pipe bomb would be pretty terrible in terms of damage, you might poke out an eye at best, as pvc has a psi rating of around 330. along those same lines (as a packaging engineer) pvc would be a terrible choice for a solid state rocket as well. One it contains so many plasitcizers that under shock stress it is quit brittle, two, it is terrible under heat extreems, and three, once it starts on fire, and it will start on fire, the vinyl chloride monomer will be released and is a pretty bad carcinogen hence its ban in the european union, its ban by the FDA for food products, its ban by for use in medical products and equipment etc.
So you are left with a rocket that will destroy itself, the vehicle its mounted on will be ruined, it will have no structural integrity to usefully direct the exaust and give thrust, and you will get lung cancer. Or you will be the laughing stock of your terrorist friends when your pipe bomb doesnt really explode, and you shrapnel will be large chunks of softened plastic that will burn people at best.
Either way, maybe you should rethink your plans.