Not bad for someone who was not much of a sharpshooter in her secondary school days and failed her National Police Cadet Corps marksmanship test.
Her passion for shooting was a slow burner, she admitted.
"It took a while for me to really like this sport. I did fail the marksmanship test, so the idea of going back to it (in CJC) was..." she added, her scrunched face completing that thought.
Nevertheless, it was a journey of discovery for the Institute of Molecular and Cell Biology research officer.
She said: "In tennis, you have to beat your opponent but in shooting, it's only yourself... everything appears the same but you can't replicate the same shot time and time again.
"You're always learning new things about yourself; how you can control your body to go against its normal bodily reactions, how during competitions everyone gets nervous but you can switch that off and go against your fight-or-flight response."
Her trigger moment came when she was invited in 2006 to join the national team, where the structured training sessions and working with a professional coach provided the ideal environment for someone with her methodical personality to excel.
She said: "I could see my scores improving, my grouping getting tighter. This is a sport not dependent on your physical attributes. It's about your level of skill."
That standard kept rising. Before the 2009 SEA Games in Laos, she recorded a new personal best - a world-class score of 384 in the 10m air pistol. That breakthrough - she does not remember clearing 380 prior to that - deepened her attraction.
A vital hurdle had been cleared. She said: "That's when you continue to push yourself harder."
It is this drive that sees Teo travel three times a week after work from Buona Vista to Safra Yishun for 10m practice. On weekends, she is at the National Shooting Centre in Choa Chu Kang for the longer event.
Team-mate Jasmine Ser, who will compete in the 10m air rifle and 50m three-positions in Brazil, was impressed not just with Teo's work ethic but also admired her zen-like approach to those Kipling impostors, triumph and disaster.