Exactly. Unless you are going to shoot 180 gr 338 cal bullets, the 338 federal is limited in bullet choices. Read the Sierra loading guide and it will tell you that the design of their bullets is for 338 win mag velocities and ranges with their bullets in the 338-06 should be limited due to this. A 200 gr SST from the 338 federal is down to @ 2200 fps at 100 yards, which is on the low end of velocity necessary for good expansion for these heavier constructed bullets.

On the other hand, many bullets of lighter construction have been made for the 358 Winchester. Not really the case for the 338 federal.