I switched over to Blazers when I got my new arrows, and at first had a problem with like every 3rd shot. It seemed that my groups were wider than the old way.

I realized that the problem was that the Blazer fletchings stood out another 1/8 inch farther from the arrow shaft than the older 4" fletchings, nd that was causing the fletchings to hit/nick my cable during the shot if I turned the nock the same way I had on my older setup. I just turned the nock so it wouldn't do that, and I was fine. I now have no problems, and am shooting better than I was in the past (but I know that could just be from practice).

I'm not saying that this is the same problem here, but it might be worth checking?