I've done quite a bit of hunting w/ .177 & .22 caliber air rifles, the most powerful of which wasn't close to a .22 short in power. Some of these high end pre-charged pneumatic air rifles are extremely accurate. What I've learned is that accuracy is the most important thing, power is a distant #2 - even the lowly .177 has plenty of power to cleanly take a rabbit or squirrel if you can put the pellet in the right spot. Not saying these rounds would be a bad choice, but make sure they are accurate in your rifle 1st and foremost. If they are not accurate in your rifle I would keep looking for ammunition.
David
David