Represented by John Archibald, Rory Smith, Fraser Christie, Steven Sinclair, Dave Campbell and David Rudd, they beat Millfield 2.5-0.5 in the final at Hunstanton in Norfolk to claim a sixth success in total in the event.
For Campbell, the victory came in his 100th match in the Grafton Morrish – the first player to reach that milestone. Smith, meanwhile, was playing in his final event as an amateur before having a crack at trying to qualify for the web.com Tour in the US as a professional later in the year.
George Heriot’s beat Warwick, Edinburgh Academy and Seaford College in the opening three rounds before claiming a 2-1 win over Capital rivals Stewart’s Melville in the quarter-finals and then beating Birkenhead 2-1 in the last four.
Christie and Sinclair went unbeaten the whole week, winning six out of of six; Smith and Archibald clamed five-and-a-half points out of six and Rudd and Campbell won three out of six.
In the paid ranks, Kevin Tway made three consecutive birdies in a play-off to seal his first PGA Tour title at the Safeway Open in California.
Tway, son of eight-time PGA Tour winner Bob, was in a three-way race for the title after finishing on 14-under alongside compatriots Ryan Moore and Brandt Snedeker.
Snedeker could only manage par on the first play-off hole, the 18th, while Moore and Tway both hit birdies on the first two shoot-out holes. The title was decided at the 10th, Tway carding a 3 on the par-4 for the win.
Snedeker went into the final round with a three-shot lead but had a torrid back-nine in which he dropped four shots as he went on to close with a 74.
Martin Laird was the highest-placed Briton but fell 31 places to joint 46th with a round of 76, including a double bogey on the par-3 second.