Cornucopia

Enchantment 
Gives a quiver, bag of pellets, or other container of ammunition an “infinite” supply of one type of ammunition – but items must be taken out by hand, one at a time. Each missile exists for one minute after being removed from the container; then it vanishes (or, if picked up by anyone but the Cornucopia’s owner, it vanishes immediately). Therefore, this spell cannot be used to make a single quiver supply enough arrows for an army! It cannot be cast on a weapon. A high-tech wizard could create a pouch that always contained one armor-piercing tracer shell; he could not enchant a .50-caliber machine-gun to fire forever.

Energy cost to cast: This is tricky, because skillful players will find many creative ways to pervert this item. GMs who find Cornucopia a nuisance may ban it entirely. In general: Energy cost is equal to 50 times the $ value, in the current game world, of the missile provided by the Cornucopia quiver. Thus, a quiver that provided ordinary arrows ($2 each) would cost 100 energy to create. 
This means that a mage in a medieval world could not make a “quiver” for high-tech ammo; that ammo is priceless in his world. A Cornucopia quiver can be made to produce magic arrows, but only if the creating mage is capable of making such an arrow – and the energy cost will be tremendous. 
Prerequisites: Enchant and two other Weapon Enchantment spells.