Well, I saw this glitch on YouTube, I tried it for myself and it worked, with Bone Meal, it changed the Metadata value from Bone Meal to a Ink Sac, this works for wool and any other items with a metadata value.

STEPS TO REPRODUCE:
1. Get a bow and a metadata item. (Bone meal)
2. Charge the bow completely.
3. Shoot the bow, right after it shoots, switch the item in the hot bar to the metadata value item.
4. It will change.

Also, I saw the bow texture got weird after some time.