To take this subject one step further to something that could be vitally important, it should be CASE HEAD UP for the fired cases!!! That allows you to keep track of what your primers look like after being fired, and for working up new loads you should be picking up each string of 5 or 10 after they are fired, and placed back in the box so you can see if they're getting a lot flatter (meaning you're headed for a KABOOM!) or mixed flat and normal, which means you screwed up something in your reloading and maybe you better stop immediately.
When working up a load, I religiously pick up each string as I fire it and put it back in the box, and for the 9x25 work I'm doing now out beyond Left Field, I take high rez macro color pictures of the case heads and append those to my chrono data.