As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
COCKPIT HALON FIRE EXTINGUISHER DISCHARGED THROUGH THE RUBBER O-RING MOUNTED BETWEEN THE DISCHARGE HANDLE AND BOTTLE WHILE SAFETY PIN REMAINED INSTALLED. GAUGE READS FULL AND THE NEEDLE REMAINS IN GREEN BAND BUT BOTTLE CONFIRMED EMPTY. O-RING FOUND DISLODGED. ALL INDICATIONS ARE THAT THE O-RING BECAME DISLODGED DUE TO EXTERNAL FORCES. THE EXTINGUISHER IS LOCATED IN A HIGH TRAFFIC AREA. REPLACED FIRE EXTINGUISHER.