I believe a shot and ball gun is like a Paradox, Colindian, Cosmos, or a well designed smoothbore,etc a gun which upon conception and purpose is designed and built to be used for both fur and feathered game. A good ball and shotgun should not be a compromise, it should perform both functions well. A ballgun is a smooth bore whose intended purpose is four footed game animals and whose specifications have more in common with a rifle (shorter heavier barrels, overall heavier no choke). By virtue of the absence of rifling a ballgun could be fired with shot, just as many shotguns could be fired with a ball but that was not their purpose. Obviously, the intentions of the maker and his client are now blurred in time.