It may be their take off on the
Corbon Pow'R-Ball bullets. These are hollow points with a round polymer ball inserted into the tip. It is to promote feeding like hardball and also to initiate expansion.
The apparently now defunct self-defense forum had a great post by a fellow whose girlfriend was a med student who did a forensics rotation. She was in on an autopsy of a fellow shot, I think, five times by police. As is usual with handgun loads, they could not tell by the damage whether the bullets were solids or hollow points or even what caliber they were as they had all penetrated completely. They were perplexed, however, by the presence of little round polymer balls they found in the wound cavities.