Removing a broken tap is definately not a job for the inexperienced. The suggestion to take it to a machine shop that has an EDM machine is the way to go. Tap extractors with the fingers are definately NOT the way to go, fingers break and then you have a bigger mess. Dental burrs and Dremel tools aren't the way to go either. How ever much a machine shop charges for the job is money well spent, your receiver will be returned to you with the threads undamaged and you won't even be able to tell there was a broken tap in the hole. I spent 40 years as a Journeyman Tool & Die Maker and during that time dealt with countless broken taps and screws.
