Ballistic calculators are for the desk top or ELR stuff .

Make a set of DA cards for the rifle and go shoot . When you get on site find the DA , pick the right card , put it on the gun , and get to shooting . It doesn't get any simpler than that . no batteries or electronic devices to worry about in the field . With a set of cards I can take my rifles anywhere and have accurate data and be shooting in no time at all , no time wasted digging through pages of log books looking for data for a day that is similar to what the conditions are now that may or may not have all the info you need at the time .

Just because " this is the its always been done " or " old school " makes it right . Long range shooting in both the civilian and military sides has gone through a huge change in how things are done and the things they use to get them done in the last 10 years . Most of the changes are really good and there is no reason to incorporate the changes into your shooting .