On September 9, 2005, at 1730 central daylight time, a Cessna 310Q, N75SM, experienced a main gear collapse following an undershoot landing on runway 25 (5,000 feet by 75 feet, asphalt) at the Boscobel Airport (OVS), Boscobel, Wisconsin. The private pilot was not injured. The airplane was substantially damaged. The Title 14 Code of Federal Regulations Part 91 personal flight was operating in visual meteorological conditions without a flight plan. The flight originated from OVS at approximately 1725. According to an inspector from the Federal Aviation Administration Milwaukee Flight Standards District Office, the pilot was returning to land at OVS after the aircraft's entry door opened on takeoff. The inspector stated the airplane touched down on sandy soil approximately 30 feet prior to the approach end of runway 25. He stated the right main gear cocked sideways when the airplane contacted the runway which was approximately 3 inches higher then the terrain. The airplane continued onto the runway and the right main gear collapsed approximately 400 feet past the approach end of the runway. The airplane then traveled off the right side of the runway where it came to rest.