Also Mike, I have been using Stu Millers calc to ballpark the arrows. So far so good. I put the stock FF+ string on yesterday and my shots were absolutely horrible. Just had one nock on the string at 1/2 inch, shoot 3 under. Shot through paper and was getting huge rips. Don't know if the arrow was sliding on the string but it clipped in there pretty good. I usually put 2 nocks on. I put the SBD string on afterwards with 2 nocks because the serving is thinner, top nock at 3/8. Set brace to 7 1/4 and was instantly shooting laser beams. Just need to fine tune it now. I was probably overspined with the stock string. Very happy now.