I have attended F1 visa Interview on 8th July at Hyderabad Consulate and my application is still under 221g administrative processing. My Visa interview went on for only a few seconds like this:
VO: Why are you going to US?ME: I am going to do my Masters in Electrical Engg at XXX University.VO: What is your area of Interest?ME: My area of interest is Power Systems and Power Electronics.VO: Do you have any backlogs?ME: I do not have any backlogs.
F1 Visa Interview
Read the comments posted the blog posts who got stamping after facing similar situation like you F1 Visa Interview 221(g) at Chennai Consulate.
Looks like there is 2 to 3 weeks wait before passport will be returned with Visa stamp. But, it depends on case by case. You might delay more than 3 weeks or might get visa in mail within 1 week. All you can do is hope and wait.