The actual muzzle velocity of most adult grade spring air rifles is between 1,000 fps and 1,200 fps for .177 cal. pellets, right up there with some .22 LR ammo. Go to
www.cabelas.com
and see for yourself.
True, but only half the story. A typical airgun pellet is only about half the weight of a .22 bullet, and has a much lower ballistic coefficient. It loses velocity much more rapidly than does a .22.
Having said that, it's still dangerous within its range. An airgun shooting a hunting (pointed-nose) pellet will kill small varmints such as squirrels. I use one to protect my garden against rabbits.
Yeah, but your average .177 pellet weighs about 8 grains, compared to 36-40 grains for your average .22LR projectile.