hornady 58gr 243 factory ammo 3750fps at muzzle as stated on box, i got 3560fps at 10' using my f1 chrony chrono. both shot from 24" barrels my tikka and there claim on the box How does this sound? I am doing this because i am checking my reloads and trying to get the velocity i want. I dont know if my chrony is off, factory ammo is over rated? or i loose that much speed in 10'...please share your opinions.