Though sailors are trained to execute in high-stress situations, competing at the Olympics still gave Reservist Information Systems Technician 1st Class Sandra Uptagrafft a case of the jitters. Uptagrafft fired her first Olympic shot on Sunday at the women’s 10-meter air pistol event. She placed 28th with a score of 378, according to a Defense Department release. Wenjen Guo of China won gold with a score of 488.1. “Once I hit the match button, it hit me that I am at the Olympic Games, and it kind of took me out of my rhythm,” Uptagrafft  said. “It took me a…