No, lathing a round. Milling a flat.
Used the (manual) milling machine today for the first time since my introductory class. Didn't quite finish all the cuts I need on the fake bolt for the Suomi -- so I probably won't be able to do the first trial weld tomorrow.
But I did use the mill successfully, without breaking anything. Now back to the books to refresh my memory on climb cutting, speeds and feeds, correct RPM for the edge-finder, etc.
The fake bolt is the top piece. The bottom is turned to the outside diameter of the barrel and pegs into the face of the bolt during the welding operation to keep the lugs aligned. Later I may replace it with a piece turned to the inside dimension of the barrel for more barrel support, but I might have to replace the turned peg with a steel rod for strength.
I also got a piece of 1/4" plate. I just might be able to do a quick run on the Tormach CNC mill -- the biggest problem right now, though, is that the desk is out of ball nose end mills. So I could do something that was a cut-out, but curved 3D shapes are not going to work well. Not until either they restock or I can order my own from McMaster-Carr.