While firearms exist in the world and are in fact fairly prevalent among certain circles. The Drarven smiths have embraced the concept and have been attempting to arm their troops with firearms to combat the Harzium Horde.
Firearms are still a exotic weapon, and with certain exception, the concept of cased ammunition has not been brought to the forefront. The party may, after exposure to Deakons character begin to develop the revolvers and other weapons that use cased ammunition. This is still up in the air as I do not want to tread on Deakons concept
Due to the complexity of the reloading process the Abundant Ammunition spells is not capable of creating full charges for firearms. At current it can keep a pouch of bullets replenished but is unable to create the black powder to fire it. It is possible that once the characters develop a cased ammunition that this magic could create the cartridges (currently Unkonown)