Does "new factory Hornady cases that had been fired one time" mean once fired brass from factory loaded cartridges?
If so, they obviously accepted a primer at one time.
However, for whatever reason, those factory cartridges could have had crimped in primers a la military ammo. So if "had a case refuse to except a primer" means you couldn't get a primer started into the cases, then you may have been fighting a primer crimp that needs removing.
Or it could be they're just on the tight side and the pocket mouths are very square/sharp. Try putting a light bevel on the pocket edges with a deburring tool and see how a primer seats then.
