An essay on shooting [based on La Chasse au Fusil By Gervais François Magné de Marolles], published 1789
http://books.google.com/books?id=-Q0AAAA...ary_s&cad=0
The author is searching for a full choke. He discounts any effect of choke, but he does talk about it being used. The treatise he mentions was by Alonzo Martinez de Espinar, arquebufs bearer to Philip IV of Spain. Philip reigned from 1621 to 1665.
While certainly not "choke" as we understand it. The concept seems to have been developing for a very long time.
Pete
