Most of the ranges near me have them set up in gullies. the longest targets are about level with the shooting bench, but the ones in between go down hill then back up hill to the longest target. My question is: Will the drop chart be accurate if I use a range like this or is it better if I find a place that is flat for 600 + yards? Also I will build a target that is 10 feet high and will set it up at the farthest distance on the flat field and move closer for each distance when shooting while always aiming at the same point then measuring each drop at the different distances. Also since I will be aiming at the top of the target am I not shooting up hill for each shot? I will be shooting out to at least 600 + yards with a 6mm Norma BR sighted in at 200 yards. I need advice on how to do this accurately so I can have a new turret made by Kenton Industries. joseph

I don't know your exact numbers, but I think if you run your 6mm numbers through Exbal or a similar program, you'll find that up to 10 degrees deviation from horizontal, the difference is zero or at most .25 MOA, even out at 600 yards. 5 degrees deviation is going to make zero difference a long ways out there. If you post your numbers, scope height, etc (all the ballistics program inputs), I'll plug those in and show you exactly how little difference small angles make.

You can use sine and cosine to figure out the horizontal distance to the target. Just measure the angle from your firing position to the target. Unless your shooting Seriously steep angles the difference will be minimal.