Re: How accurate are the online ballistics calculators???
I would think that JBM would be plenty accurate enough to get you on target at 600 yds. The errors are more likely to be in things like scope height above bore and actual bc compared to inputted bc, than in JBM errors. But if I understand you right, you are not using bc, rather you are using 100 and 200 yd drops. Using those drops, scope height would be inportant. Also, there would be some error in the drops you are using. Still, I'd think you'd be at least on a 600 yd target, unless it's a really small target.