When trying to determine if .22 or .177 is the better air rifle caliber, you have to first ask what you’ll be using the gun for and what performance metrics are most important to you. Most target shooting is done with .177 rifles, while hunting is more often done with .22 rifles. The .177 caliber has higher initial velocity with lower muzzle energy, and the .22 caliber has a lower initial velocity with more muzzle energy. They’re both great calibers; you just need to ask yourself what your main purpose for the gun is going to be before deciding on a caliber.