Don't know if you're a handloader or not, but I'm gonna throw the .280 Ackley Improved in here for the heck of it......Factory cases are available, and you've got something a little different from the rest of the crowd. Probably actually achieve actual 7 Mag velocities with a non-belted 40 deg. shoulder case. Load the full gamut of .284 bullets............
Should be able to re-chamber a .280 with no problem.