On July 22, 1994, approximately 1250 Pacific daylight time, a Grumman G-21A Goose, N327, sustained substantial damage when the pilot lost directional control after landing at Bremerton, Washington. The commercial pilot and his two pilot-rated passengers were uninjured. There was no flight plan filed for the flight, which was conducted in visual meteorological conditions. The pilot was practicing landings at Bremerton. Damage included left landing gear collapse, left wing tip and spar damage, keel damage, and structural damage around the left main landing gear. The pilot stated that while rolling out after landing, while at about 20 mph in a three-point attitude, he experienced a loss of directional control to the left, which he corrected with right rudder, right brake and left engine. He stated that he over- corrected, which resulted in a turn to the right.