For Sir Gar it concluded two days of intense competition involving seven twenty minute 15 a side games, six all of which were won in style with one draw.
There were first day wins over Bishop Vesey GS 17-0, Bradfored GS 38-0 and Filton College 10-0 before the triumph of the second day.
After drawing with Ivybridge 0-0, beating both Hartpury 19-0 and favourites Colston's 14-7, the final proved a rousing affair in front of a large crowd.
Sir Gar captain and centre Rhys Williams made the vital break that created a try for full back Rhodri Mason and fly half Jon Griffiths added a conversion and a penalty.
Amongst many outstanding performers, back rowers Nicholas Cudd, Matthew Evans and Lloyd Phillips stood out up front as well as locks Haydn Pugh and Lou Reed whilst the inventive Williams and half backs Justin James and Jon Griffiths impressed behind.
Williams was named Player of the Tournament for his sharp running and all embracing defence.
In the Plate final, a try by fly half Steffan Rees was enough to give Neath the edge 5-0 over Marlborough.
WEDNESDAY 14 DECEMBER
Filton College 5 Truro College 8, John Cleveland College 3 Swansea College 0, John Cleveland 8 Truro 6, Filton 0 Swansea 3, Swansea 7 Truro 3, Filton 5 John Cleveland 15
Ivybridge College 0 Coleg Sir Gar 0, Hartpury College 0 Colston's 10, Coleg Sir Gar 19 Hartpury 0, Ivybridge 0 Colston's 8, Coleg Sir Gar 14 Colston's 7, Ivybridge 5 Hartpury 6
Coleg Sir Gar 10 John Cleveland 3
Neath Port Talbot College 5 Marlborough 0