Some of the guys that build accurate rifles will tell you that there are some calibers that are far more challenging than others. Further believe that there are calibers that certain riflemakers won't accept an order to build as their experience has shown that it takes to many hours & barrels to finally get the high performance their reputation demands.
J Barsness wrote a pretty good story interviewing Malcom Forbes, D"Arcy Echols and some others about this question.
