Horrible velocity, but that's the whole point; it's a sand-bagged round with only a fraction of a propellant in it.
Even in a "hot" 22LR round, you're stretching your luck to get much results at 100m, so taking away half of the powder from that makes it not much more accurate than throwing a football at something.
The purpose of these rounds is to hit something extremely close, like a squirrel at 10m away, without making too much of a bang. It needs to be out of a bolt/revolver, too, because it doesn't produce enough gas to cycle the action on a semi-auto. If you try to put these in something like a Ruger 10/22 or Remington 597, you'll have a stoppage/jam every round.