The 28-year-old's dipping 20-yard volley doubled his side's lead at Plainmoor on Saturday as they ran out 3-1 winners over Torquay to remain at the top of the table.
And Constable, who is now just 12 short of the club's all time goalscoring record, says he has not scored a better goal for the club.
"I can't remember a cleaner strike than that," he told the Oxford Mail.
"There are a lot of times when the ball sits up like that and you think 'should I have a shot or not?', but I don't think I've hit a better one than that.
"I just needed to make sure I got the cleanest connection I could. I didn't want to see it go out for a throw."