17th century (if that's what you mean, the 1600's, but i think you really mean the 1700's) and even 18th century powder horns were quite subjective, there were MANY variations from very rustic super simple to highly ornamented and engraved. all will be "hysterically correct", it just matters if you have a need for a specific horn type due to reenactment persona or era or or just for personal aesthetic satisfaction.