If you are able to get 275 lbs for your max naturally, I believe you will have no problem reaching your goal of 315x1, if not better. The dbol you're taking is going to sky rocket your strength within a very short time. The test will continue to help your strength level over the entire cycle.
Something to keep in mind..your muscle will get strong much faster than your connective tissue and joints. So be smart. As you get strong, be careful. It's easy to get hurt. Increase the weight slowly. I would increase by about 5% per wk.