Content provided by Michiel Meyer, hosted with permission

A fresh primer must now be inserted into the unprimed, cleaned case. Whether you use the priming insert of your reloading press, or the more convenient hand priming tool. Whichever tool you use, make sure to seat the primer deeper than the bottom part of the case. The primer must never stick out of the case, or even be flush with the case. I use a LEE hand priming tool for the job.