try this - be careful
The tool RREgge is referring to is generally known in my neck of the woods as an "easyout" and also referred to as a "bolt extractor". After you drill a hole in the center of the headless bolt, the easyout's reverse threads are designed to bite into bolts/machine screws and unscrew them as they go.But there is danger thar. If the bolt is seized/jammed/stuck, an easyout, which is made of fairly brittle tool steel, may snap off without warning - they can't handle too much torque. If they do snap off, chances are you are going to have a real headache trying to get the broken easyout removed from it's pilot hole. Happened to me 2 weeks ago while I was trying to remove a headless bolt. Had to grind out the easyout with a dremel tool (tool steel is hardened thus drills are then useless) before I could drill out the stuck bolt. Miserable stuff.Mike