It's not just one piece of brass. I've had similar results to the OP. I use Hornady brass for reloading, but refuse to use once fired brass from their factory ammo.Yep based on the failure of one (1) piece of Brass, out of millions, Hornady brass has been deemed crap, and of no use to anyone. It could not have been anything else.
And here I though the junk brass was Remington, or was it Federal? No it must be ...................?????????????????
I had piece of LC with a case head separate. I avoid it all now,
The OP can accurately say Hornady brass from factory ammo is crap. But not all Hornady brass is crap.