The most essential data for ballistics calculations is projectile speed. A chronograph is the best tool for the job. Whether you're handloading for the range or building arrows for the hunt, the Xero C1 Pro chronograph provides the speed data you need to hone your craft. The Xero C1 Pro chronograph makes ballistics calculations easy. This compact device fits in your back pocket, measures projectile velocities from 100 fps to 5,000 fps and provides the data you need t