That makes as much sense as 3D-printing snowflakes and then compressing them, rather than just making ice-cubes in your freezer.
Where are you going to get the nitrocellulose goo to extrude the powder granules from?
Where are you going to get the nitrocellulose goo to extrude the powder granules from?
That's really a good analogy. OTOH I really like shaved ice and dippin' dots. And where do glaciers come from?
Jeez, how do they make powder in the first place? It's got multiple goo stages in it. Nitrocellulose is a resin. I suspect propellant can be incorporated into filament. I'm not willing to go into too much detail in public, but solid propellant grains can be made to burn pretty quick without detonating. Also some things are more efficient and also have a higher regression rate than double-based powder. Look to hobby rocketry for some ideas. The sky is the limit. so to speak. Think outside the brass.
That being said, the overall effectiveness of modern ammunition is pretty hard to beat, and bench loading technology is readily available. Today there may be no point to 3-d printing ammo other than for bragging rights...computerized 3d printing can be easily be tremendously slower than traditional human-actuated machining. Speaking from bitter personal experience. 3d printing works best when it replaces multiple steps in the design or production flow, or allows some similar shortcut.