Ruger has issued a safety advisory for the 9mm American pistol. Some pistols with over 10,000 rounds fired have excessive wear on the barrel hood and corresponding slide surface. It can lead to a crack in the slide at the rear of the ejection port. If the barrel or slide has peened edges Ruger will replace it. I attached Ruger's announcement.
https://ruger.com/dataProcess/APRetrofit/index.php
https://ruger.com/dataProcess/APRetrofit/index.php