I keep ripping fletchings off. Always the same one on each arrow. I've glued them back on, but don't think that's the issue as it's the same one on every shaft. I'm thinking I'm knocking the arrows wrong. I'm shooting an older Darton, no idea what model as my uncle gave it to me. I put a Whisker Biscuit on it this past summer. I'm a right handed shooter, when knocked the cock vane sits on the left side, parallel to the ground. Any help guys?