There was a NZ company as I recall that was 3-D printing complete titanium high powered rifle silencers a few years ago. Being a non-regulated item in Kiwi Country, these things are considered disposable and Nylon printed .22 rimfire cans are a hardware store item that you just throw away and buy another for $10 when it plugs up with lead, wax, and carbon. Anyway, this company was trying to establish importation to the United States market through Canada, not sure if it worked out or not. Our import laws forbid class 3 firearms but NAFTA gets around that somehow. Pretty cool that all the complex baffles, ports, clips, and outer tube could be built up with basically a CNC wire-feed TiG welder to create a one piece silencer capable of withstanding very high pressures with no internal leaks and no unnecessary weight from spacers. Additive manufacturing I think IS the wave of the future, even if some subtractive finishing techniques may still be necessary for threads or precision surfaces.