Black powder is the key explosive component within a firearm that enables it to function, but in larger amounts this alchemical material can be quite destructive on its own as well. A single dose of black powder is enough to power a single shot from most one-handed and two-handed firearms, while 10 doses are required to fire a cannon. Black powder is often stored and transported in kegs (which hold 100 doses), but in this quantity the powder itself becomes dangerous. Exposure to fire, electricity, or a misfire explosion causes black powder to explode—a single keg that explodes in this manner deals 5d6 points of fire damage to anyone within a 20-foot burst (DC 15 Reflex half ). Storing black powder in a powder horn protects the powder from explosion.
Pathfinder Roleplaying Game Ultimate Combat. © 2011, Paizo Publishing, LLC; Authors: Jason Bulmahn, Tim Hitchcock, Colin McComb, Rob McCreary, Jason Nelson, Stephen Radney-MacFarland, Sean K Reynolds, Owen K.C. Stephens, and Russ Taylor.