REST API stops responding to AJAX calls

[Gary Bailey]

I am working on a Chrome extension for my company use, which pulls all Epics in a given project and release, then pulls the associated development stories and displays a table of epics and their associated stories, with key information highlighted (status, hours, etc).  In both cases, I am using a recursive function to build an ajax request with the "startAt" and "maxresults" parameters used to pull the epics and stories in blocks.

All works well for the epics, however in the case of the stories, some of my queries just hang - I get a "200" response code, but the server just never sends the data.  I've tried querying by epic link and by just pulling everything for the project.  I'm expecting around 160 epics and 450 stories to be returned.  A sample request string as it's currently configured:

https://mysite.atlassian.net/rest/api/2/search?jql=((issueType=%22QA+Story%22)+OR+(issueType=%22Dev+Story%22)+OR+(issueType=%22Patch%22))+AND+project=%22RDO%22&startAt=0&maxResults=500&fields=key,status,summary,fixVersions,assignee,aggregatetimeestimate,aggregatetimeoriginalestimate,aggregatetimespent,aggregateprogress,customfield_10013,issuetype

This link works perfectly if I just paste it into my browser.  There has to be a better optimised way of doing this!