As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
OPERATOR REPORTED SUDDEN ENGINE ROUGHNESS IN CRUISE. LANDED WITH OUT INCIDENT. MECHANIC NOTED RT MAGNETO MODEL S6RSC-25P, PN: 10-500556-101 TO BE IN OPERATIVE. VISUAL INSPECTION CONCLUDED APPROXIMATELY 15 TEETH WERE STRIPPED OFF OF DISTRIBUTOR GEAR INSIDE MAGNETO. NO FOREIGN OBJECT DEBRIS NOTED INSIDE MAGNETO. CAUSE UNKNOWN. INSPECTED LT MAGNETO DISTRIBUTOR GEAR, NO DEFECTS NOTED. REPLACED RT MAGNETO WITH NEW.