Ysterhout Dot Net
Do the box tracking test first, before the tall target test, because if there is a tracking problem it will skew the tall target test results. The tall target test is primarily for calculating the scope correction factor.
The best backing to use for these tests is the packaging from large appliances - refrigerator, washing machine or dishwasher. Tall refrigerator packaging is the best.
Make sure your scope tracks properly. Do this even if you have the most expensive scope, do not assume the scope is perfect. Test it.
There are detailed instructions online to perform a tall target test.
Follow the instructions from Bryan Litz on how to perform a tall target test, and derive the correction factor for your scope to use on the drop chart.
The tall target test is the most important scope test for a Long Range shooter to perform. The importance of the result, and applying the result to the drop chart, cannot be over-stated.
The result of the tall target test is two-fold :
The elevation adjustment factor can then be added as a column to the drop-chart, to show actual elevation adjustment next to the calculated value.