How to post traditional form into iframe within an Angular 4 app

I'm attempting to do a traditional form post into an iframe from within an Angular 4 app and it's simply posting into a new tab. I had trouble posting the form at all until I added ngNoForm to the form element so I'm assuming that I need to do something else (maybe to the iframe element?) My form tag looks like:

<form 
  ngNoForm
  method="POST"
  action="http://some.url"
  target="responseFrame"
  >

My iframe tag looks like:

<iframe id="responseFrame" name="responseFrame" src=""></iframe>