Hey fellas, so just when I thought I had all I needed to dial my scope for 1000 yard shots, Leica 1600B, Kestrel 3500 and Shooter ballistics app. I found out about the difference between G1 and G7 ballistic coefficients... Now my head is spinning trying to figure out which one my ammo uses and what that number is... I've been reading that Bryan Litz book Applied Ballistics for Long Range Shooting has tons of testing on ammo and the G1 vs G7 differences and which one to use for specific bullets. Is this book a must buy if I want to be accurate out to long ranges 700+ yards??