yesterday went out to the range anxious to use my new 35p chrono. shot several strings and noticed my averages stayed about the same, but my extreme spread seems to creep up each string. i don't know if this is because of the barrel/chamber warming up or something else. i've been reloading for a few (+15)years and have finally come around to using a chrono. it is really nice to know what your actual velocities are!