C# - Using HttpWebRequest To POST To A Form On An Outside Server?

I am trying to simulate a POST to a form on an external server that does not require any authentication, and capture a sting containing the resulting page. This is what the form looks like:

<FORM METHOD="POST" ACTION="/controller" NAME="GIN">
<INPUT type="hidden" name="JSPName" value="GIN">

Field1:

<INPUT type="text" name="Field1" size="30"
maxlength="60" class="txtNormal" value="">
</FORM>

This is what my code looks like:

ASCIIEncoding encoding = new ASCIIEncoding();
string postData = "Field1=VALUE1&JSPName=GIN";
byte[] data = encoding.GetBytes(postData);
// Prepare web request...
HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create("https://XXX/controller");
myRequest.Method = "POST";
myRequest.ContentType = "text/html";
myRequest.ContentLength = data.Length;
Stream newStream = myRequest.GetRequestStream();
// Send the data.
newStream.Write(data, 0, data.Length);
StreamReader reader = new StreamReader(newStream);
string text = reader.ReadToEnd();
MessageBox.Show(text);
newStream.Close();

Currently, the code returns "Stream was not readable".