I keep track on a couple of Glocks I shoot all the time, mainly to see how long they will go before things start to break.
Other than that, I usually dont bother. Although its usually not to hard to figure things out if you shoot them on a regular basis, and know what you shoot when you go.
“The enemy is anybody who's going to get you killed, no matter which side he is on.”
― Joseph Heller, Catch-22