Powder horn A powder horn was a container for gunpowder , and was generally created from cow , ox or buffalo horn . The term may also be used for any personal container for gunpowder , regardless of material or shape , for which powder flask is the strictly correct term . Typically there was a stopper at both ends , in later examples spring - loaded to close automatically for safety . The wide mouth was used for refilling , while the powder was dispensed from the narrow point . In some cases the point was closed and the mouth used for both , with a powder measure , a type of scoop used to dispense the powder , and in others both ends were open and the horn merely used as a funnel . The horn was typically held by a long strap and slung over the shoulder . Although forms of pre - packed cartridge s go back to the Middle Ages , many forms of early firearms did not use them , or users preferred to load each charge before firing . Most cartridges were prepared by the gun - owner and a container was still needed for the gunpowder used to make them up . There were other methods , including small cloth bags containing the correct amount for a single shot , that might be carried on a bandolier ( again requiring a container for a supply for refilling ) . An important safety concern was that when reloading a muzzle - loading gun soon after a shot there might be small pieces of wadding burning in the muzzle , which would cause the new load of powder to ignite as a flash . So long as no part of the loader faced the end of the barrel this was not dangerous in itself , but if a spark reached the main supply in the powder flask a fatal explosion was likely . Various precautions were taken in the design and use of powder flasks to avoid this happening . Some types of guns required two different forms of gunpowder ( such as a flintlock with finer priming powder for the pan , and different powder for the main charge ) , necessitating two containers , a main horn and a smaller " priming horn " . In particular , the powder horn was rendered obsolete by the innovations brought about by Hall , Sharps , Spencer and the later development of self - contained cartridges that were developed and marketed successfully by Oliver Winchester , after which manufactured cartridges or bullets became standard . Powder horns were also used for the priming of large naval guns , and in blasting operations ; apparently sometimes the horn shape was merely a convenient form of funnel in such cases , and was open at both ends and not used as a container . The use of animal horn along with nonferrous metal parts ensured that the powder would not be detonated by sparks during storage and loading . Horn was also naturally waterproof and already hollow inside . In America , a number of period horns dating from the French and Indian war s throughout the American Revolution and beyond , have been preserved in private and other collections . Many decorated examples shed light on the life and history of the individuals that used them , and can be classified as a medium of folk art . Powder horns were often decorated , most often with engraving , making a form of scrimshaw , which was sometimes supplemented with colour , and less often with carving . External links . Historic Deerfield , Powder Horns from The William H . Guthman Collection