Shannon started the second half with intent, immediately applying some real pressure on Dungannon, pressure that paid off four minutes into the half when Minogue touched down for his third try of the afternoon under the posts.
With Gavin adding the resulting conversion, Shannon's lead now stretched to 24 points. 
To the visitors credit, they replied expertly with a try of their own when James Gamble touched down under the posts in the 50th minute, which McCaughey converted to leave the score at 27-10.
The visitors added a another converted try minutes later after applying consistent pressure on the hosts. Shannon's northern counterparts were now back in the game with the scoreboard now reading 27-17. 
Dungannon tails were up and with the hosts looking to repel any fight back from the visitors and incredibly, it was Oisín Minogue who touched down again for his side in the 62nd minute and as Gavin had done all game, the fly-half was flawless from the tee, with the score now reading 34-17 in favour of the Limerick side.
The contest began to fizzle out following Minogue's fourth try but Dungannon did manage a late consolation try through Sam Montgomery with the clock in the red.
McCaughey was unable to convert and referee Jack McNiece sounded for full time with Shannon running out 34-22 winners on the day.   
Elsewhere, UL Bohemians advanced to the Division 2B decider following a 27-15 win over Clogher Valley.
Old Crescent have been relegated to 2B following a 16-10 loss to Sligo. UL Bohs will face Sligo in the final with the winners promoted to 2A.
Thomond will also remain in Division 2C following a 21-13 defeat to Bective Rangers.