After a considerable delay I am back with some updates on my Winchester 21 DR 45-70 project. Since my last post (last year) I have completed all the 3-D scans of the prototype receiver, trigger plate, top lever, monobloc, and forearm shoe. We have just verified and modified the CAD data to input to the CAM program for the receiver. It turns out that the CAD data was prepared expecting a 4 axis CNC milling machine while my machinist only has a 2 axis machine. This caused considerable delay in rewriting the program since the milling machine tried to pick up data inside the block of steel and would plunge the bit into the metal causing quite a mess. Anyway, this is something for you to keep in mind if you try this. The learning curve has been steep for me but I think I am finally ready to finish milling out the receiver. The first thing we did was extract the data for the outline of the receiver being careful to be exact on the water table and the radius for the hinge pin. We set up the EDM wire cutter to cut out two receivers at once (see pictures below). You can see from these pictures we are literally starting with a solid block of 4340 steel alloy. The wire cutter saves a tremendous amount of milling time and does a great job on the flat or surfaces that require a precise radius. I highly recommend you use this step first.

EDM tank. You can't see the metal block but it is in a bracket below.

Tank emptied with one cut completed

Both cuts made from block of 4340 steel alloy.

Receivers as released from the initial EMD cut.