Bow of Tuning

This initially appears to be a ordinery +1 bow, but each successfull hit in real melee causes the bow to tune itself into the users Strength, to hit & damage bonuses, becoming a strength adjusted bow. The tuning starts at a 10 strength and adjusts by one strength catagory with each successfull hit.
The Bow loses its tuning by 1 category per day if unused.
If the users strength, or user, changes then the bow must be retuned from 10 again.
The Bow can only be tuned to one person at a time, if it is tuned to one person and someone else starts to use it the origional tuning is lost. Value 20000GPS