Trainor posted a superb six-under-64 score to go two strokes ahead of Damian Mooney with David Higgins, current leader of the Lexus Race to Mount Juliet, and John Kelly sharing third place, a further two strokes back.
Birdie threes at the second and fourth holes set the former Warrenpoint Senior Cup player on his way before two further birdies and two bogeys left him out in two-under-par 32.
He dropped another shot at the par four 11th before that storming finish in which he covered the last four holes in five-under.
Golden eagle threes flew in at the 15th and 17th holes, separated by par four, and Trainor finished in style with birdie two at the last hole for an inward trip home of 32 shots.
This win moves him up to 8th in the Lexus Race to Mount Juliet.
Top 20 in Lexus Race to Mount Juliet (in association with Ping):1 David Higgins 15,498.332 Damian Mooney 12,083.893 Michael Collins 7,814.644 Michael McDermott, 7,477.425 Eamonn Brady 7,427.926 John Kelly 6,245.067 Brendan McDermott 6,072.498 Barrie Trainor 5,691.769 Neil O’Briain 5,252.5010 John Dwyer 4,379.0811 David Ryan 4,188.2512 Peter Martin 4,025.0013 Robert Giles 4,023.8314 Graeme Dunlea 3,541.7215 Mark Staunton 3,443.3316 Glen Robinson 3,406.0417 Eddie Doyle 3,382.0818 Donal Gleeson 3,266.7419 Leslie Walker 3,250.2820 Simon Thornton 3,250.00