Thanks so much for all the comments. I really appreciate them.
Jim, the info about the sorts of rifles that Wister thought his American buyers would like is in a letter that he wrote to Georg Friederich Hölzer on October 1, 1737. It's translated and quoted in Rosalind Beiler, Immigrant and Entrepreneur: The Atlantic World of Caspar Wistar, 1650-1750 (University Park: Pennsylvania State University Press, 2008), 145-146.