How do you expand "until" the edge of something you're scaling hits a specific vertex?

Often times when I’m scaling part of a mesh, I want it to perfectly align with something, yet I know I’ll never get it to…or can I? Take for instance this example screw. I want to scale the flat part of the cone until one of its vertices perfectly touches the first part of the screw part. How can this be done?

Screw A.blend (509.3 KB)

Change your snapping to vertex. Select the face, scale the face, then hover over the edge point of the screw and hold the CTRL key down, the face should scale so one of the points snaps to the same position.