One pipe and a little gun powder come out as six missiles at a Level 2 bench. Cheap to keep a SAM Site fed, but the pipe is gone for good once crafted.
Ask for missiles in whole batches. Every craft hands you six, whatever number you typed, so a single missile costs the same metal pipe as the full batch, and one missile past a batch costs a second pipe. The gun powder lines up at any count; the pipe is the only thing worth counting.
The blueprint costs little scrap at a Level 2 bench, so learn it the day the SAM Site goes on the roof. A site with power and no missiles stops nothing.
Watch out
Crafting them is a one-way door. Recycled missiles give back a pinch of powder and only rarely the pipe, so turn spare pipes into missiles, not the ones a gun or a rocket was waiting for.
That pipe could also be a whole high velocity rocket. If roof fights against players are what keep going wrong, the launcher is the better home for it; if minicopters are, the batch of missiles is.
