With all equipment, it takes a little bit of time to sort it all out. Over the last weekend I was shooting the FITA Field two day, just outside Llandovery, Wales, and did O.K.. On the evening of the first day, was eyeing over the kit in prep' for the second day and thought I could see a strange mark on the nocks. Hmm..maybe not. Anyway, shot the second day and things were alright, but as with the first day, a few arrows that were shot behaved in a peculiar way and certainly didn't land where they were supposed too, based on the feel of the shot. With about four targets to go, and having just seen another arrow *do funny things*, I took a closer look at my arrows and this strange mark on the nocks. The mark was a black streak on the side of the nock, away from my eye when locating them on the string. With a diagnostic by myself and Paul Wickenden, we both came to the conclusion that the new style plastic finger spacer was pressing against the side of the arrow when at full draw.

We then looked at the angle required to do this and we were both surprised at how little *out of the straight line* it had to be before the spacer touched the arrow or nock. Both of us were amazed. Both of us looked at Pauls but no mark could be seen, but as I pointed out, the spacer could be pressing on the arrow rather than the nock depending on the anchor/finger position/depth. We both agreed that to trim the leading edge of the spacer would solve this issue.
Last night, I did just that. I kept the length of thespacer the same but trimmed a length off the front angle so that there was no way the spacer copuld force it's way onto the arrow at full draw. Results were that this odd arrow I was getting (spewing out of bow in a dead straight line, left or right) ceased.

Groups which were pretty good got better.
I have imparted this finding as I'm sure there are many many more archers on the forum who are unwittingly having the same problem, with unexplained arrows going left or right following what felt like a perfectly normal shot.
The result of the spacer pressing on the arrow will show the arrow bending at full draw, hence the strange deflection when the arrow leaves the bow..a bit like top finger pressure on the arrow..but this time on the side of the arrow.
With the spacer being black and carbon arrows being black, it might take a bit of close scrutiny to see any ware/rub on the arrows or even if black nocks are being used.