On May 14, 1995, at 1340 mountain daylight time, a Mooney M20F, N9399V, sustained substantial damage during an acceleration test prior to takeoff at a private airstrip near Frederick, Colorado. The pilot and one passenger were not injured and one passenger received minor injuries. The aircraft sustained substantial damage. Visual meteorological conditions prevailed for what was planned as a local area personal flight and no flight plan was filed. According to the pilot, he was doing an acceleration test prior to departing, and when he got to about 70 knots he pulled the throttle and applied brakes. He said the aircraft slid on the grass and collapsed the landing gear going through a fence and ditch. According to the aircraft operating manual, normal rotation speed is 60 knots indicated airspeed. Examination of the accident site, a 2,800 foot dirt airstrip, by this investigator revealed witness marks which showed heavy wheel marks on soft dirt and grass for a distance estimated to be 700 feet prior to impact with a fence and ditch. The witness marks indicated the landing gear collapsed after the aircraft went through the perimeter fence and entered a road side ditch. The aircraft came to rest on a county road which borders the south side of the airstrip.