To answer your question, son.....
I would have to refer to an episode of American Shooter, with Jim Scoutten. They had an episode where they showed a Federal Ammunition Production Facility. Obviously, they showed very limited amounts of the production process because ammo manufactures are relatively secretive about their processes.
But the operation was not like a bunch of reloading presses, but more like your described in you beer bottle analogy. The casings did a kind of slolom thru the various powder, seating, and crimping dies. It reminded me of driving thru orange cones if you were testing the handling of a race car. Dig?