I have a long range competition coming up this weekend. My primary goal is to collect dope on my new handloads for the purpose of truing my Kestrel w/ AB and some other iPhone ballistic calculators I use. However, it occurred to me that while there will be quite a few targets at varying ranges, almost all of them will be at a downward angle. Some of the angles are steeper than others. Is there anything I should know before I start collecting dope for truing purposes on angled shots. Will I need to multiply the actual distance to target by the cosine before inputting into the software for truing purposes? Are angled shots inherently flawed for truing? In addition, I will be shooting over a somewhat steep valley that can produce upward drafts very near the firing line. Is that going to screw up my dope for the purpose of truing? Please educate me. I get too few opportunities to shoot, so its important to me I make the most out of it. Thank you.