I just purchased the same gun and had the same question so I called the customer service line (800-264-4962). They refer to the chokes as "short" and "long range" turkey chokes. According to them the short range (XFull) is .593 and the long range (XXFull) is .565
I haven't unboxed the gun yet but can't wait to spend some time with it. Have you selected a load yet? I have read of some choke/load combo's on this board that seem pretty consistent for the Affinity3 shooting TSS and heavy shot, but not too much about the lead loads.