Also If your gunsmithing school demands that you demonstrate your fabrication prowness... I would tell you to take a piece of old barrel the appropriate size and create the threaded shank and then with much elbow grease and great precision, cut the extractor groove with your hands and the appropriate files...
One of my metalworking final exams while apprenticing with a master gunsmith over 30 years ago was that I was given a rough cut piece of steel and my objective was to make it a perfect one inch cube within .001 inch using only a bench vise, a micrometer, and any file that I chose to use... IT TOOK ME HOURS! and more than one attempt... how many more I won't say! [img]biggrin.gif[/img]
Wish I still had that cube [img]smile.gif[/img] but I lost it during my travels while on active duty...
Here is a drawing that you may find helpful... (sorry but it is as clear as I have... if anyone has a copy of this drawing that is in better focus please let me know)
