I suggest you approach the department of the university you are interested in and ask them. It depends on the subject you are doing. I`ve been trying for a year to get in for a self-funded PhD in Psychology with a 2:2 and MSc, but have had little success. Perhaps you should try a small university as the major universities tend to admit mainly foreign students with few places available. I`ve approached a university that has recently acquired university status, and it seems quite hopeful that I will get a place.