The Thunder fell behind 8-0 early in the contest however a pair of Jaeden Marwick touchdown passes to Preston Bews and Colton Klassen along with a Klassen rushing major gave the Thunder a 28-8 lead at halftime.
A wild second half ensued as the Rifles rolled up 10 straight points to cut the Thunder's lead to 28-18 however Regina never lost control of the game.
Marwick found Bews for another aerial touchdown for a 34-18 lead and Regina quarterback Sawyer Buettner - in relief of Marwick - put 10 more points on the board to put the game away at 51-22.
With the win the Thunder improved to 4-2 while the Rifles dropped to 1-5.
The Thunder will enjoy a bye week and then visit the Calgary Colts on Sunday, October 4.