The process of making the upper receiver has been slightly changed from the first parts we made. We are doing the internal grooving on the cnc lathe. After programming the lathe the first thing to do is test the program and inspect the groves as cut. This is one of the test pieces we made to perform this task.
To get to this point we needed to order and get in an adapter to allow us to cut the lathe chuck jaws to the proper diameter. This is the tool that allowed us to accomplish that task.
With the jaws cut to the proper size it is time to get started
The part is sized to the correct length and grooved to the proper diameter for the bolt then the outside diameter is cut.
Once this is completed the part is turned and then the front barrel support groves are cut in and once again the out side diameter is turned.
The upper receivers are now ready for the next op.
As usual great work and thought process on making the tool (s). Fantastic workmanship. Harry