As noted earlier in this thread, I have pulled the bullets on a bunch of "blue box" Federal ammo and not only often found the exterior appearance of many bullets different, but sectioned them and found differences there as well. Which is why I long ago came to the conclusion that they use whatever bullet they can obtain inexpensively.
Have found somewhat the same deal with Remington "Core-Lokt" ammo since around 1990--when they quit producing the heavy-jacketed Pointed Soft-Point CL bullet. Some of the early post-1990 Core-Lokt ammo featured Hornady Interlocks.
