I think factory rounds would be OK...
I've often thought of doing up 25-06, 30-06 and 35-06 (35 Whelen) with identical rifles.....vary the barrel contour and/or length to make up for the difference in bores to make the weight and balance the same......although the 30-06 would do what the other two do right out of the gate..so practicality could not be the impetus for such an exercise.....