I suggest that you "SHOOT" your drop chart with YOUR rifle and BULLETS you plan on using. This will give you the bullets arc as it goes down range.
I would use a white paper or cardboard at least 4 feet high and put your 200 yd. target near the top so you can see where your longer range shots hit. Then you have all your groups on one target.
I sighted mine at a 200 yd. zero then while shooting at the "SAME" target "EACH" time at all the ranges. You need to hold your crosshairs on your 200 yd. zero for each distance then you can measure the drop from 200 yds. and then 300 yds. then 400 yds. Shoot 5 shot groups and measure down from your 200 yd. zero to the "CENTER" of each group below. This will give you the most accurate arc of "YOUR" bullet.
I only shot at 200 yds then 300 yds. then 400 yds. This gave me the arc that my bullet had going down range. I also gave the Turret maker the altitude and temperature and humidity of where I shot the target. What he did was to make the velocity and other info for their computer program match the arc ( my measured drops ) of my bullet when making my custom turret.
When I first tested the custom turret it was dead nuts accurate out to 400 yds. Later when I was able to test its accuracy at much longer range it was dead nuts accurate out to 900 yds. The 900 yd. gong was a large one. How big I'm not sure, but the 700 yd. gong was 7 inches in diameter and 3 different guys hit it almost every time shooting 5 shots each.
Testing new Vortex custom turret. - Georgia Outdoor News Forum
PS: I called Vortex and spoke to Paul. He was the one that adjusted the program to make the custom turret. Great company and great customer service.