I see that not everyone (anyone) agreed or found what I found. So I offer the following. First I used the JBM ballistics program using the following parameters to check my previous answer; bullet, 55gr Hornady VMax; environment 85 degrees, 30" barometric pressure, 15% humidity (dry here), 4900' elevation, pressure was corrected (this is the little check box in the environment section). Scope height 1.5" above bore. For speeds I used the min and max speeds from the Hogdon website for H380 powder which were 3507 and 3713 fps. The table below shows how the bullet heights will spread with different sightin distances. The difference shown on the right is conservative as ballistics tables don't let you sight in for one velocity (say the slow one) and then shoot a faster bullet, ie, sighted in at 200 is the same for both velocities. We all know that the faster bullet would hit somewhat higher than the slower bullet if you first sighted in with the slow bullet then fired the faster bullet. Therefore the differences shown are conservative and off by some distance that I can't measure easily. I have done the calculations for 4 different sight in differences; 300, 200, 100 and -1.5 inches at 50 (essentially a 0 degree horizontal barrel). The use of 50 yards won't help the OP as a zero at 50 is the same as a zero at 200, and the spread generality was too large for such a short distance, my mistake. Using longer distances, like the 650 I eventually used, can increase the ladder height to over 11". There is a difference, but at 325 yds it is probably not over 3.5 to 4". That is why I quit using straight ladder tests and use an OCW like test as shown at the link below to find nodes on targets at closer ranges.
http://forum.accurateshooter.com/ind...opic=3814361.0
Bullet drop at these velocities at 325 yds
Zero @ 3507 fps 3713 fps difference
300 -1.7 -1.5 .2
200 -7.3 -6.4 .9
100 -10.5 -9.0 1.5
-1.5"@50 -17.9 -16.1 1.8
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