I think that a "sinker" EDM would be a good choice for cutting the cam surface on lug abutments. The problem now becomes machining the electrode but that would be simple on a 4th axis VMC. A friend has a VMC with 4th axis and is hinting that I need to buy an older ram (sinker) EDM.
I think the process that makes pistol barrels is called "ECM" for some form of electro-chemical machining. A company that does this was setup at the SHOT Show in '98.