Seeking Feedback on Research Topic Outside Department/University I am about to start my third year in an economics PhD program and I'm starting my dissertation. Part of the dissertation involves subject matter that none of the faculty in the department know enough about to give specific useful feedback. 

I want to ask faculty (who I know are knowledgeable) from different departments/universities  for some basic feedback on my current progress before plunging more into the research topic blindly (with only my understanding of the literature to guide me).  

I'm thinking I will ask my current committee members to introduce me to anybody they know who might be helpful. If they don't know anyone I will consider cold-emailing. 

So my question is:

Is my current plan a bad idea and is there a preferred alternative approach?
I too had a topic which was outside of the expertise of my committee. If you are set on your topic, this seems like a good approach. After talking to your current committee and getting their buy-in on the plan, you could also approach other faculty at your current institution to tap their networks.

Another way of doing some networking to get feedback is to attend local or subject area conferences. The big AEA conference is pretty difficult to use for networking, but you could make contacts at these other conferences which could be helpful. Especially once you get your work to a poster stage.

I would also like to advocate a second idea, which is to change topics to something more similar to your committee's area of expertise. While this is not what I did, I definitely saw the merits of it as my friends who took this approach were able to coauthor with their committee, have more useful RA experiences, and come out with more lines on their CV for the job market.