Fellas, hope someone can give me some pointers here. I took the scope on it's first outing to the range today. Shooting 150 grain FMJBT the point of impact was about 9" high at 100 yds. With the elevation factory set at 0 I only have 5 mils of down travel to lower the POI. Do I have to adjust the elevation to -5 then set zero and progress down in increments from there? Any advive much appreciated.