The extra weight (50% heavier than a standard 22 long rifle 40 grain round) is a first in the rimfire realm.
The round appears to be a 22 short case with a long 60 grain lead round in it.
CCI 22 LR ammunition is ideal for target practice or small game hunting when noise is a concern.
The CCI Velocitor uses a standard 40 grain bullet, but reports to offer a surprisingly high 1435 feet per second, or about 200 feet per second above the standard.