What is the pressure BEFORE the regulator? What is the pressure AFTER the regulator? What size piping do you have? What provisions did you allow for proper support (Clevis hangers spacing?) What is the actual total fixture demand of this building?
When you know the actual pressure after the pressure regulator AND the actual piping internal diameter then all you need to do is plug in the numbers to find your velocity in FPS and knowing what piping material your using I can tell you exactly if the velocity is exceeding the piping manufacturers recommendations and if this is what is causing the hydraulic shock waves (water hammering)