Side Plate Smear on Wraps ?

[Greybark]

I am shooting 45-50 DF shafts out of my BW PTFX bow , 50lb at 28in draw and 29/1/2in arrow length . Am getting a wee bit of noise now and again and there is a little side plate smear on some of the arrow wraps . The shafts are tapered.
  Is this caused by being slighlty under spined ?
  Thanks for your consideration.

[Pheonixarcher]

My guess would be slightly over spined, or a nock point that is slightly off, or possibly a tad bit too much nock pinch from the string fingers if shooting split. Have you bare shafted, or paper tuned the bow? You may also want to check your nock fit, and try using a tie on nock point both above and below your arrow.

[bamboo]

yup---
with the longer draw--

[Orion]

Yep.  Quite a bit underspined.  Most bows will shoot an overspined arrow quite well, but they're not as accommodating of underspined shafts.

[ISP 5353]

I would guess you are under spined.