Vortex Viper BDC
I have a viper 6.5x20x44 with the BDC reticule. Last week I got to try the BDC out to 300. I was shooting a 7mm Mauser with 162 grain Hornady at 1700 ft ASL and 2459 fps, sighted in at 100 yds at 700 ft ASL. I compared the Viper BDC chart to the Ballistics program on my Iphone and actual shooting out to 300 yds. Three hundred yard group was three shots in 2.1 inches with two within .60 inches, ooops. All three methods weere within .5 MOA or 1.2 inches elevation. I have not tried the BDC out to 500 but the chart and the Ballistics program are within .4 MOA. We will see. I really like the scope so far.
RRH (retired rotor head)