|This article is about an older version of DF.|
(This article also covers bolts, arrows and quivers for completeness' sake.)
Crossbows are the only ranged weapon that dwarves can carry. A dwarf will open fire at a range of about 20 tiles, but the bolts may travel further and hit something by accident. Crossbows can fire at targets on higher or lower z-levels; doing so hurts the range slightly, even when firing from higher to lower levels. There seems to be a "line of sight" rule, of about a 1:1 ratio (height difference to distance from edge of level) but the exact formula is not known.
A bolt does a fine job at piercing the internal organs of a creature while also doing some damage to outside parts. This is of limited use against creatures without organs, such as magma men or undead, but excellent against creatures with more "normal" internal anatomy. Occasionally a bolt will get stuck in a target; the only known use for this is that a wrestling dwarf may grab the bolt and twist it in the wound.
Once you tell a dwarf to use a crossbow (either from the ilitary/eapons sub-menu, or by iewing the dwarf and accessing the oldiering sub-menu), he will pick it up if he has either the hunting skill enabled or if he is in the military. He will then pick up a quiver and bolts, preferring metal bolts if available. A dwarf can carry one stack of bolts in his hands, and one in his quiver.
Dwarves often do not return to base and pick up more bolts if they run out if there are enemies nearby; instead, they will enter melee.
Construction and quality
Crossbows can be constructed from wood, bone or metal. Wooden and bone crossbows are created at a bowyer's workshop; metal ones at a metalsmith's forge using the crossbow-making or weaponsmithing skills, respectively.
The quality of a crossbow is added to the marksdwarf/ambusher and hammerdwarf skills. The material used in construction of a crossbow does not affect the damage done when firing, but does affect the damage done when it is used as a melee weapon.
Using masterpiece ammunition will not result in a bad thought for the maker, whether or not it breaks, nor will trading it away. However, losing even one masterpiece bolt out of an original stack of 25 will, if at 1/25 of the usual penalty (which is still sizable; see Quality/Masterpiece for a full discussion). If a single masterwork bolt left outside is stolen, or if a wounded enemy escapes with a masterpiece bolt stuck in them, it's possible to cause a tantrum. For this reason it may be wise to, as policy, either forbid masterwork ammo until the maker has churned out several stacks of them, or just trade them away.
According to this forum discussion, marksdwarves are able to wield their crossbows one-handed, and so can use another item in their second hand. If they use a buckler, they may carry it plus an extra set of bolts in the off hand; if they use a shield, they still suffer no penalty to the crossbow usage but cannot carry the extra set of bolts.
Metal bolts are created at the metalsmith's forge and require the weaponsmith labor enabled. Wood and bone bolts are created at the craftsdwarf's workshop and require woodcrafting and bone carving labors, respectively. Higher levels of skill will tend to produce higher quality bolts. The material and qualityVerify of the bolts (not the crossbow) affects the amount of damage done.
If you decorate a stack of bolts, the same decoration will be applied to every bolt in the stack simultaneously. In older versions this allowed to generate stacks of huge value - value of decoration was multiplied by amount of bolts in the stack. This has been fixed now and decorated bolts are no longer that valuable.
Quivers are made of leather at a leather works. Dwarves equipped with a crossbow will automatically wear a quiver if one is available, and carry a stack of bolts in it. This allows a dwarf to carry one extra stack of bolts, typically bone or wood training bolts in the hand, and metal ones in the quiver.
In adventure mode, a quiver can hold any number of arrows and bolts.