A quick Google using "primer unlocked accident" found these easily.
<a href="http://www.canard.com/ntsb/LAX/88A050.htm" target="_blank">accident 1</a>
<a href="http://www.canard.com/ntsb/FTW/89A017.htm" target="_blank">accident 2</a>
<a href="http://www.eagletribune.com/news/stories/19991114/LN_005.htm" target="_blank">accident 3</a>
It's enough for me to make sure the primer's locked and stays locked....