Is there a book out there that deals with external ballistics math/simplified? I need to start at the basic of basics. I have not done any trig since high school. Should I just go get a high school trig book and review it first? I forgot all that stuff, don't really know what the heck subtends means. Milirads and Degrees, all that is trig ain't it? Other than that are trajectory calcs just basic algebra? But for starts let me outline what I think I know. 1) you gotta know with precision the muzzle velocity of your projectile, B/C, weight. 2)You got to get a trajectory chart 3) You got to know the wind effect 4) Up and down slopes 5) Accurate distance to target Then it all has to go to adjusting the scope or holding over or off. Did I forget anything? So how is all that done lightning fast in the field?