However, not everyone has access to a 1000 yard range. I tune my BC, muzzle velocity, or both when using Exbal so that the program predictions match my field shooting data, usually using 1000 yard dope, which I get with enough shots to be reasonably certain that I know what the 1000 yard dope really is. Quote:The error budgets start getting very tight near 1,000 yards (with most of the cartridges we shoot), and leaving the chute with known inaccurate data cannot help hit probability. Yes, Sierra is one of the few which provide G1 data in velocity ranges. Once you get away from the experimentally derived (as opposed to calculated) Sierra data, similar multiple ‘velocity banded’ G1 BC’s for other bullets gets pretty scarce. Quote:My testing with Sierra Matchking and the DTAC 115 grain bullet show near perfect correlation between Exbal and on-target results when using multiple ‘velocity banded’ G1 BC’s.

Just my 2 cents worth.Īre you going to be in Sacramento in March? Yes, some dweebs are going to screw this (and other inputs) up, but I for one am not going to continue to pay for software written to protect incompetents from themselves. I find Gerald’s assertion that we can’t be trusted to input the correct BC insulting. The error budgets start getting very tight near 1,000 yards (with most of the cartridges we shoot), and leaving the chute with known inaccurate data cannot help hit probability. I am not sure I agree with your assertion that it’s not a big deal because I am going to take the shot anyway.

And you are right about the G1 and G7 predictions being close until the transonic range, as Bryan shows so clearly in his book. My testing with Sierra Matchking and the DTAC 115 grain bullet show near perfect correlation between Exbal and on-target results when using multiple ‘velocity banded’ G1 BC’s. If you run Exbal with a BC based on Bryan's Litz's testing, rather than the manufacturer's BC, which is usually, well, optimistic, Exbal will give you an elevation prediction which is very close to, say, JBM Ballistics using a G7 BC. And even then, it's not a big issue, because you're probably going to take the shot anyway.

That's not a major issue until you're shooting near the range where the round goes transonic. Originally Posted By: LindyThe biggest advantage of using a G7 BC is that it more accurately predicts velocities downrange.

Exbal nightforce ballistic program