On May 21, 2011, at 1025 mountain daylight time, N6850B, a Cessna T210M, was substantially damaged during a gear up landing at Pueblo Memorial Airport (PUB), Pueblo, Colorado. The commercial pilot was not injured. The airplane was registered to and operated by the pilot. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight conducted under 14 Code of Federal Regulations Part 91. According to the pilot, he departed Pueblo to conduct air work in the local area. After a normal take off, when the landing gear was retracted, he heard a "very unusual sound" that continued until the gear cycle was complete. He also noticed an amber gear warning light. The pilot leveled off at 7,500 feet and began to troubleshoot the problem by referencing the emergency procedures in the Pilot Operating Handbook (POH), which included two attempts to manually extend the gear. The pilot then checked the hydraulic fluid reservoir and it was empty. He then advised the tower of his situation and they suggested that he place a quart of engine oil in the hydraulic fluid reservoir and re-attempt a gear extension. The pilot added the oil and made another attempt to manually extend the landing gear, but to no avail. The pilot then flew by the control tower and tower personnel told him no gear was visible. The pilot said he then made a no-gear landing as directed by the POH on Runway 26R. According to the Pueblo Airport Operations Incident/Accident Report, the pilot landed with the nose gear down and locked and the main landing gear not down and locked. The airplane landed approximately 1,000 feet from the runway threshold. Upon touchdown, the nose gear remained extended and the main landing gear retracted. The airplane skidded on the belly and the tail before it came to rest approximately 400 feet east of taxiway A10. There was no fire. A Federal Aviation Administration (FAA) inspector performed an examination of the airplane and reported that the left horizontal stabilizer was substantially damaged. According to a representative of the repair facility that fixed the airplane, an o-ring in the nose gear actuator piston had failed. In addition, a seal in the emergency extension system had also failed. Once the failed o-ring and seal were replaced, the landing gear functioned normally.