American Jamie Lynn Gray set a pair of Olympic records en route to capturing gold in the women's 50-meter three positions rifle event.
Later in the day, Jessica Rossi of Italy easily won gold in the women's trap, setting a world record by hitting 99-of-100 shots in the competition
Gray finished fifth in her event at the 2008 Beijing Games, but opened up Saturday's qualification portion with an Olympic record score of 592, besting Poland's Renata Mauer's score of 589 set at the 1996 Atlanta Games.
The 28-year-old then topped Du Li's record score in the finals with a mark total mark of 691.9. China's Du had set her record of 690.3 in winning gold at the Beijing Games.
"I thought 'Oh, that's cool but there is still a final,'" Gray said of setting her first record. "You don't come here to shoot an Olympic record, you come here to shoot the best you can."
Gray finished fifth in last weekend's 10m air rifle final.
Serbia's Ivana Maksimovic captured silver with a final score of 687.5, while Czech Adela Sykorova was third after posting a mark of 683.0.
Du ended 13th in failing to defend her Olympic title, finishing two spots ahead of American Amanda Furrer. Czech Katerina Emmons, the 2008 silver medal winner in this event, ended 32nd.
Rossi set world records with her qualifying and final total. She hit all 75 targets in the opening round and only missed once over her final 25 shots. The previous Olympic record total of 91 was set four years ago in Beijing by Finland's Satu Makela-Nummela.
It's the first Olympic medal for the 20-year-old Rossi.
Slovakia's Zuzana Stefecekova, who held the total world mark until today, finished in a tie with Delphine Reau of France and San Marino's Alessandra Perilli, but Stefecekova claimed silver in a shoot-off.
Reau finished ahead of Perilli for bronze.
Kimberly Rhode, winner of the women's skeet event on Sunday, finished ninth for the U.S. and teammate Corey Cogdell placed 11th. Rhode is the owner of five Olympic medals, including three gold, but none of them have come in the women's trap.