Homemade Greek pita bread, recipe may be off.

Recipe calls for 3-cups flour and I should get 7-8 pitas, 8" diameter, 1/4" thick when rolled out. I can only get 8 pitas at 6 1/2"-7" diameter, 1/8" thick. After the rise and the dough is divide and rolled in to balls the recipe says to let rest 10-min. before rolling dough out to keep from spring back. I've waited 20-min. and still have spring back when rolling out. Any thoughts?
Thank you.