Despite missing the overall ladies' winners' prize by 4 points, to the overall winner; Liu Ming Shu, the Kampala golfer finished fourth overall
Byamukama was two strokes better than Denis Anguyo and Silver Opio who tied second with 74 gross.
Sh5m is up for grabs by the top performers in the one-day event that will have players using only four clubs.
Kenya's Stefan Andersen played six-under-par 66 to claim the lead from day-one leader Simon Ngige
Action in the four-day tournament resumes on Thursday
The four-time Uganda Open champion was two strokes better than former amateur winner Phillip Kasozi and Herman Mutaawe
Ugandans are up against over 50 foreign entries that include defending champion Madalsito Muthiya
This year’s open also offers a chance to a number of rookies
The nine Ugandans who made the cut shared a paltry sh9m
He is determined to repeat his 2014 heroics where he emerged winner with 281 gross
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