What was found
AT FL250, CABIN ALT HORN WENT OFF. RAN QRH REGAINED PRESS WITH CARGO OUTFLOW CLOSED. MECHANIC STATED LOWER CARGO DOOR SEAL FAILURE. FOUND THE LWR FWD CARGO DOOR SEAL ON THE LOWER EDGE PUSHED UNDER. LEFT SEAL AS IT WAS FOUND FOR FURTHER EVALUATION. SECURED DOOR SEAL AS NEEDED IAW SMP. PRESSURIZED A/C WITH RIGHT HAND PACK ONLY TO 3.0 PSI, NO DEFECTS NOTED, NO LEAKS FOUND ON DOORS. ACCOMPLISHED EXCESSIVE CABIN PRESSURE LEAKAGE TEST IAW B727 JRH. FOUND TO BE WELL WITHIN LIMITS PER TEST AND PG 8-29, FIGURE 6. OK FOR SERVICE.