Originally Posted by ol mike
I did some longrange practicing from a mountain top down onto the valley floor last fall and at 400-5-600-yards you don't hold over very much at all.
That depends on your angle. Most angle shots are less than they seem. A 30 degree angle looks more like a 40 or 45 degree angle and a 45 degree angle looks like a 55 or 60 degree angle, almost straight down.
At 30 degrees you want to multiply your straight line distance by .86 to get your horizontal distance which is what you compensate for. and at 45 degrees you multiply the straight distance by .71
For a 30 cal, 200 gr Accubond with an MV of 3200 (typical 300 RUM load)
Your bullet drop difference at:
30 degrees and 300 yds will be about 2.2 inches
30 degress and 600 yds will be about 16 inches
45 degrees and 300 yds will be ablout 4.1 inches
45 degrees and 600 yds will be about 28 inches
And you want to hold under, not over.
These are oversimplified calculations and ballistics programs figure sight hieght into the calculation, and at more extreme ranges elevation differences should also be calculated.
Bottom line, inside 300-400 yds you can guesstimate fairly accurate. Just run some numbers and make a little drop interpolation chart. For farther shots you should get the equipement and software or else you're basically shooting and hoping.
Also you should figure the angle of your shot through the body. When shooting down hill if you aim for mid body you'll actually inpact higher toward the back but your bullet will travel down through the body through the vitals. If your shooting up hill you want to hold well under and catch the bottom of the chest.