Recently, the screws (#6-32) on my red dot both sheared off. I was lucky on one. It broke off with a piece that I was able to use a pair of diagonal cutters to grip and remove. The second one broke inside the screw hole. It also broke off center and at a slight angle. I was not able to to get a good dimple to get a drill bit centered or to get any bite from the drill bit. I thought about it for several weeks, and came up with the idea to use a 2mm end mill bit and then a conventional 2mm drill bit to get deep enough to use a small screw extractor. I broke 2 end mills, but removed enough material to get the drill bit to bite without damaging the threads. It probably took less then 15 minutes to get the second screw out with no damage. I basically used the endmill to create a dimple for the drill bit then drilled down far enough for the extractor to work.
What I used...
I already had a cheap drill press and vice
I already had a 5/64 screw extractor
2mm end mills
cobalt drill bit assortment
What I used...
I already had a cheap drill press and vice
I already had a 5/64 screw extractor
2mm end mills
cobalt drill bit assortment