What was found
AFTER SUCCESSFUL COMPLETION OF 1ST LEG AND 1 COMPLETE CYCLE OF THE GEAR, TOOK OFF ON SECOND LEG. WHEN GEAR HANDLE WAS RAISED GEAR DID NOT COME UP. GEAR CONTROL C/B HAD POPPED WHEN GEAR WAS RAISED. MATCHED CONDITION WITH GEAR HANDLE DOWN AND TRIED TO RESET C/B. THE C/B WOULD NOT RESET. RETURNED FOR LANDING. ALL OTHER HYD SYS WORKED. TURNED POWER ON AND ENGAGED CIRCUIT BREAKER. CIRCUIT BREAKER REMAINED ENGAGED. JACKED ACFT & PERFORMED 20 GEAR SWINGS WITH NO FAULTS NOTED. INSPECTED WIRING FOR SQUAT SWITCHES & GEAR CONTROL VALVE WITH NO FAULTS NOTED. LANDING GEAR OPS CHECK GOOD AT THIS TIME IAW MM 32-01-00.