There is no need to input the tapered base into the Kestrel. If you measure scope height at the bell of the scope, the most your error will be is 1 – 2 clicks at 1000 yards. This can be offset by measuring to the center of the windage turret instead of the bell of the scope. It is more likely that the scope click errors will do more harm than this will. Here is some reading that might help: http://www.longrangehunting.com/forums/f19/applied-ballistics-faq-167008/.