Ok so rifle is Rem 700 varmint with 26" barrel. Ammo is hand loads I had from another rifle and have lost all load data. My chrony is broke so I shot two different 3 shot groups at 480 yards. Both held 3" group with vertical variance only 1/2". With 100 yard zero, 2" scope height, temp was 80* 54% humidity and elevation of 800 feet. What's puzzling me is groups only dropped 24-1/2". When run through ballistic program I have to use a 3550 fps velocity? That seems really high to me. Using .48 for BC what am I doing wrong?