Thickness of frames in xymatrix (for a beamer presentation)

Question

I have an xymatrix that looks like this:

xymatrix{
A & B & C & D \\
  & A & B & C }

I would like to put a red frame around the second column. I've been able to accomplish this using the following code:

xymatrix{
A & B & C & D \\
  & A & B & C  
\save "1,2"."2,2"*[F:red]\frm{}\restore }

What I'd like to do is make the frame thicker. Any pointers on how to do this? Sorry if the above code is sloppy or inefficient; I'm pretty new to this.