Graham was asking for specifics as far as the rifle setup so we can help you out. It could be poor bedding or barrel/stock contact, loose base, bad scope, could have a long throat from the factory and you just haven't found the load it likes, or you could have a bad barrel. I have owned a few rifles that wont shoot, but it could usually be tracked to one of the above problems. If you had someone else shoot it and you were able to duplicate its poor performance, you ruled one very important factor out.
Kirk R