I just posted an article titled, Considerations & Math for External Adjustable Riflescopes. It was published in the last two editions of the Single Shot Exchange Magazine. It can be accessed at http://www.texas-mac.com/Considerations_and_Math-for-External-Adjustable-Riflescopes.html.

Wayne

NRA & TSRA Lifetime member. NSSF member. Author & Publisher of the Browning 1885 BPCR book.
See www.texas-mac.com