|1||Normal + weak/cheap bow string breaks, otherwise string weak.|
|5-6||Deep wound. Save vs. Adversity after combat or bleed to death|
|7+||Crippling wound, and arrow passes through, may hit another.|
I decided that only a cheap bow string should break immediately. A standard bow should merely get frayed, which means the PC can either restring the bow or risk using it for a while; a second damage roll of 1 means the bow string breaks as the arrow is fired, although the arrow itself still strikes the target. We can apply the same effect to a sling, although a sling can’t be restrung, but requires much more serious repair. The stave of a bow itself won’t break as badly as a cheap sling unless the bow is really shoddy, in which case it probably also has noticeably reduced range.
But you know what? There is a kind of missile weapon that might act more like a massive, two-handed melee weapon: boulders thrown by giants or siege engines.
|Damage||Boulder Damage Effect|
|1||Normal + weak/cheap siege mechanism breaks.|
|5-6||Knock prone/stun, plus bleeding from spiked spheres.|
|7+||Broken bones, Move 3 and -1 to actions until healed.|
Giant-thrown boulders and siege weapon ammo are pretty much area effect weapons, anyways, so I didn’t give them the “pass through” effect of an arrow, although if you were rolling for a ballista or javelin flinger of some kind, you should feel free to apply results from either table, as you feel appropriate.
Note, also, that siege weapons and giants typically do more than one die of damage, so those broken bone results will be more likely.