I went out today to see if I could figure out my bc. First thing I did was verify my muzzle velocity. I came up an average of 2754. Next I shot at 100 yards and got an average velocity of 2640 I didn't go Any further shooting over the Chronograph because I wasn't sure him much I was going to trust these numbers to produce my final BC. next I shot a 3 shot group at 200 and another at 300. All I had was a short box so I didn't think I had enough room to shoot 400 so I shot a 3rd group at 350. Once I had all this done I came home and used the jbm calculator to find the BC using the velocity I got just for kicks. And it told me. 809! I obviously didn't think that was right but I ran that number through the shooter ballistics program on my android. It said that at 350 yards I should haves 12.7 inches of drop. My drop was 10.5 inches at 350 and 6 inches at 300. Next thing I tried was putting in a BC of 770 in my program and I came up with the same numerals as I did with 809. Whichever leads me to believe the parameters of my expirament were too small to give me the precise info I am looking for. Can someone with some experience give me their opinion? Thanks.