60-64", toward the shorter length for hunting, and toward the longer length for target. It doesn't seem like any of the modern trad bowyers are making recurves longer than 64", although I occasionally see some longer ones that were made 50 or more years ago. 70" is a common recurve length for Olympic recurve bows. As far as accuracy is concerned, I think the longer the better. I guess you could paraphrase the answer the old Texas ranger gave when asked why he carried a .45: "Because they don't make a .46!"