What was found
EMERGENCY EXIT POSTED ON CAS CLIMBING THROUGH 8000'. LEVELED OFF AT 10,000' AND RAN THE ASSOCIATED QRH. AFTER ABOUT 4 MINUTES THE CAS EXTINGUISHED. RETURNED TO THE AIRPORT AND LANDED WITHOUT INCIDENT. OBSERVED THAT THE EMERGENCY WAS SECURE AND THE EXTERNAL PRESSURE VENT FLAP WAS CLOSED. DETERMINED THAT THE EMERGENCY EXIT PIN IS SIGNIFICANTLY HARDER TO PUT IN AND REMOVE. CHECKED THE PROX SWITCH RIGGING AND IT IS GOOD. PERFORMED MULTIPLE OPS CHECKS WITH OPENING AND CLOSING THE DOOR WITH NO DEFECTS NOTED. PRESSURIZED THE CABIN AND TAPPED AROUND THE SWITCH WITH NO DEFECTS NOTED AS WELL, COULD NOT DUPLICATE SQUAWK, WORK DONE IAW AMM: 52-71-21.