00:05:15 | This is part of the Putting Rounds on Target DVD set. In this segment, Bryan discusses a few points about chronograph accuracy. This portion is a little dated because it was filmed before Labradar and Magnetospeed devices were available. Nevertheless, the second part of the video talks about the statistics of muzzle velocity, in particular Standard Deviation (SD). What is SD, how does it compare to Extreme Spread (ES), and how the two are related. Understanding this content will help you make better decisions with your chronograph test results.