i need help with my game

I am trying to get an array of images to move in sequence. however when the value of i changes, one the barrel stops rolling and another one starts. how would i get them to continue rolling after the value of i changes. i have tried many different loops but i cant really get it to work.

Private Sub tmrbarrel_Timer()
If Image3(i).Visible = True Then
Image3(i).Left = Image3(i).Left + 25
End If
End Sub

Private Sub tmrcounter_Timer()
i = i + 1
Image3(i).Visible = True
End Sub

Thanks in advance