Commercial jacketed bullets can vary a great deal. A guy that shoots F class down in LA had some sierras one time that they must have forgot to put a core in.
Benchrest shooters first buy from a certain lot. Then they weight every bullet and put in groups, then they uniform the primer pocket and flast hole, then they cut the brass to length and deburr it, then they weigh every charge, and they vary the seating depth of the bullet depending on conditions. It is crazy what all you can do to a cartridge.
I say if you want the utmost accuracy you must weigh the bullet.