I also am not sure about the foc but I have used A C C's for years and love them I use mostly 4 inch with a drastic helical, I fletch my own. I have also used 3 inch 4 fletch with success. I personally think that the 371's would be a little too heavy for 62 lbs but that is my opinion only at 62 lbs I would use 349's or no larger then 360. Again that is only my opinion. I have taken 12 deer with the same shaft.