There is only one commercial chambering that would clean up the existing chamber.It is the 270 Weatherby. The case is longer and its various dimensions are large enough to clean up the 270 chamber without setting the barrel back. It would require the bolt face be opened for the larger rim. It might require some minor adjustments for proper feeding.
The only other commercial chambering is the 270 WSM. This would require setting the barrel rearwards as the WSM case is shorter than the 270 win.
Now if you wanted to go with a wildcat there are more options. Cost could be prohibitive. A custom reamer may have to be purchased along with custom dies. This activity can be fun and stimulating and great brain exercise. Will one of these make a difference? Probably not as the performance of the 270 Weatherby would be hard to beat.