A .22 will, of course, make plenty of perhaps undesireable noise compared to something like a spring-air gun if a degree of stealth is of interest. On the other hand, something like CB Longs or CB cap .22 ammo (CB Longs are preferable IMHO) will be almost as quiet as a pump-up or high powered CO2 air rifle. That is, of course, a terrific advantage of a .22 arm, a very high degree of flexibility and efficiency.

Air guns are fascinating, though, and in many instances can be used and practiced with at home in your garage or basement safely and without attracting attention (observe all applicable local laws and ordinances of course, and use a proper backstop, target trap, and eye protection). Practice makes perfect (and is fun), as they say. For further information on air arms of all kinds, I can highly recommend the Air Gun Digest, which use to be published every few years. Don't know if they publish it anymore, but the old editions are absolutely fascinating if you have the slightest bit of interest in the sport/hobby.