SMA ON LNDG ROLL OUT HAS R MAIN GEAR BREAK AWAY. TURNS ACFT OFF RWY INTO GRASS.

Narrative

I TOOK MY CHILDREN UP FOR A SIGHTSEEING RIDE. THE VISIBILITY WASN'T GREAT SO AFTER APPROX 30 MIN I DECIDED TO RETURN TO THE ARPT (I77). I ENTERED THE PATTERN MIDFIELD DOWNWIND. HAVING ALREADY GONE THROUGH MY PRELNDG CHKLIST I PUT IN 10 DEG OF FLAPS. AFTER CALLING BASE I PUT IN ANOTHER NOTCH OF FLAPS. AFTER CALLING FINAL I PUT IN THE REST OF FLAPS AND CHKING THE VASI I HAD RED OVER WHITE. I NOTICED AN ACFT IN POS FOR RUNUP SO I CALLED A SHORT FINAL; DID A SCAN AND HAD RED OVER WHITE AND 70 KTS. ON TOUCHDOWN I FELT NOTHING OUT OF THE ORDINARY. I FELT THAT BOTH MAIN GEAR WERE ON THE GND SO I APPLIED THE BRAKES AND PULLED BACK ON THE YOKE SO AS TO MAKE MORE PRESSURE ON THE MAINS. AT THAT TIME I FELT LIKE SOMETHING GAVE OUT OR I RAN OVER SOMETHING. THEN THE L WING DROPPED AND A VERY LOUD SCRAPING NOISE STARTED. MY FIRST THOUGHT WAS A FLAT TIRE. I WAS GOING TO RETRACT THE FLAPS BUT LOOKING DOWN AT THE WING I REALIZED THAT AS CLOSE TO THE GND AS IT WAS I BETTER NOT. I WAS STILL ROLLING OUT STRAIGHT SO I FIGURED IT WAS BEST TO GET THE PLANE INTO THE GRASS. I APPLIED FULL L RUDDER AT THE SAME TIME TURNED OFF THE FUEL AND CALLED TO THE FBO THAT I WAS ON RWY WITH PROBLEMS AND EVERYONE WAS OK AND TO SEND HELP. I FINISHED THE SHUTDOWN AND EXITED THE PLANE. I WALKED DOWN THE RWY TO FIND THE WHOLE WHEEL-BRAKE-STRUT ASSEMBLY LAYING THERE. AN INSTRUCTOR FROM THE FBO GAVE US A RIDE TO THE FBO WHERE AFTER ABOUT A 20-30 MIN WAIT THE OWNER SHOWED UP. HE INFORMED ME THAT THERE WAS NOTHING I COULD DO SO GO AHEAD AND LEAVE; THAT HE WOULD CONTACT ME. I HAVE HEARD NOTHING TO DATE.