As Barik, drop your Turrets and shield, play a cat and mouse game where youre the mouse, let the turrets do damage meanwhile and keep your shield or cover between you and the turtle.
Walk through his shield, hook him closer to your teammates. In a 1v1 watch out for his turrets, try to stay out of their fire angles and you will out-dps him then with the help of your shell heal card and extra hooks.