So I had a crazy thought: as the Xero is triggered by sound, then could you put it down range infront of and just off to the side of the target (shielded of course) and measure velocity at distance? I dont have mine yet to experiment, but am assuming the sonic crack could trigger the unit and register as the velocity before the muzzle blast arrived down range. Maybe use air rifle setting or? Not sure exactly how the various settings work on the unit.