I had a cracking day out shooting with WMS in Wales yesterday; very good day and very informative (if a little wet). But not without its shocks...!
I was using my 6x47 lapua and throwing 105gr rounds down range at a chrono'd 2855fps. Using 2 ballistics programs that Andrew (the WMS chap) and I had we could not calculate the elevation and windage for any ranges beyond the zero distance with the figures I had speed and BC. Through a series of calculations and tests at ranges from 100yds to 644yds we finally calculated that the rifle was throwing out rounds at around 3125fps! That is a serious chronograph error of 270fps!!!
Has anyone else had a similar issue with inaccuracy of their chrono that they are aware of?