Can someone explain velocity variation, zero height,zero offset in the bullet selection tool to me? I assume the velocity variation is a value the chronograph gives you?
The velocity variation is a function of temperature affecting velocity. If you know that a 1 degree drop in temp costs you 2 FPS, enter 2 here. If your powder is not temp sensitive, just enter 0. The zero offsets are how far off your zeros are at your zero range. If you are .25 high at 200 yard zero, enter it here. Go to Sean's site, there is a manual to download.
