I am working on a 7mm-08 load for an 18" barrel set up. Using the reloading manual velocity, and the Hornaday calculator, I have an estimated FPS but need to get a dope chart dialed in. If a Chronograph is a must have for this (and nice to have for reloading), any recommendations on brand? if there is another way using the data from the book and calculator, please let me know and I'll try that. Thank you.