The tournament is the last of the major events on the Champions Tour this year and Bryant is going after the second major title of his senior career.
Bryant shot a 29 on the front side and his 62 established an 18-hole record at the Crosswater Club course.
"Probably one of the top five ball-striking days in my career," said Bryant, who broke the course mark of 64 established last year by both Tom Watson and Joe Ozaki.
Loren Roberts, who won the Senior British Open last month, eagled the 10th hole from 171 yards out and was in second place with a 7-under 65.
Watson -- who at age 59 missed out on a chance at golf history when he fell to Stewart Cink in a playoff at the British Open this summer -- shared third place at 67 with Tom Lehman and defending champion Fred Funk. Watson won this tournament six years ago.
Greg Norman, citing back spasms, withdrew from the tournament prior to the start of his round.