IBO at 313 at 29"
65 lbs and a 360 grain arrow

Is the 313 set on 70 LB with a 350 gr. arrow?
If yes, here is an estimate:

-5 # draw weight subtract 12 fps
+ 10 gr. of arrow weight subtract 3 fps
- 1 1/2'' of draw subtract 15 fps (27.5'' draw)

313-30= 283 fps