According to the accident pilot, he took off for the local area personal flight at 0925. After performing a few maneuvers and sightseeing, he returned to the airport, entered the traffic pattern, and planned to land on runway 33. Initially, no traffic was observed in the pattern. However, just before announcing "turning base" another airplane pilot announced that he was turning base for runway 33. The accident pilot observed the other airplane, which was ahead of his airplane, and he extended his downwind leg for spacing. Thereafter, the accident pilot indicated that he needed to perform a series of "S" turns to "delay landing" while heading back to the runway's center line. The pilot stated that he arrived over the threshold with above normal sink rate and below normal forward speed. The airplane bounced on the runway, the pilot lost directional control, and the airplane ground looped. The airplane came to rest in the grass with a collapsed left main landing gear. Upon the pilot's subsequent examination of the airframe, he observed that the left wing spar was cracked. The pilot acknowledged in his completed "Pilot/Operator Aircraft Accident Report" that the airplane's final approach flight path was not stabilized, and he should have performed a go-around.