Drop chart help

[JARHEAD1371]

I have used a few different drop chart calculators and I'm having some problems. I've adjusted as many variables as I can and still getting adjustments that are usually 1-2 MOA off. My zero is 300 yds and I have shot groups for drop at 400, 500, and 600 yds. Can someone help me out with drops, and 10 mph wind drift, out to 1000 yds? Thanks for your help.gun)

7mm SAUM
168gr Bergers
28" Brux barrel 1-8.6 twist
56.5 gr RL17
velocity 2990-3020 fps

300 yds 0 moa
400 yds 1.5 moa
500 yds 3.75 moa
600 yds 6.25 moa