I created my first dedicated crossbow squad last night and set them up with ten targets in their barracks, hoping many would shoot at once. I'm observing that only one shoots at a time, and always at the same target. They all /seem/ to be getting experience (up to level 2 marksdwarf after a couple of realtime hours) but I'm wondering why only one goes at a time. I think my ammunition settings (train with bone, which are constantly being produced, fight with metal, which I should make more of...) might be off.
Ten targets in a row, all designated as rooms assigned to the squad (T but not I or Q) and a cabinet nearby defines a proper barracks (that overlaps most of the archery "rooms") with TIQ for the squad. I had originally channeled in FRONT of the targets to allow bolts to be reused, but then they stopped using the targets, which I think is because they need to be able to access the front of the target physically? So, I constructed a floor over the channel.
I'll report back if tweaking ammo or changing anything establishes a more impressive firing line. Speaking of ammo, if I've designated bone bolts for training and metal bolts for combat, do the dwarves carry 25 of each and use what is necessary at the moment, OR will they keep bone as long as they're training, and then delay when I order them to station or kill while they drop the bone and pick up some metal ones?