Sounds like you should be shopping for a .22lr. If it's your first gun, I'd suggest you buy a bolt action. Most accurate for the money, safe, and easiest to clean. CB longs are not silent, but quiet if the barrel is full/proper length.
Compared to airguns~similar to some, louder than most. Spring-piston (break-barrel) air rifles are very quiet, and available at over 500fps (PAL required). The good ones are expensive, and require airgun-rated scopes. PCP, or any CO2/pneumatic air guns go off with quite a "crack" sound and yes...some high-power PCP guns (again, PAL req.) are comparable to the sound made by CB longs..dare I say, sometimes louder. SO, for the money...assuming you've done your homework on discharge laws in your area, I'd say a .22lr is your best bet. It'll also be cheaper to buy/scope than high-powered air guns. Make sure the gun is chambered for .22 lr and .22 long, or you may be forced to load them one at a time. Look for rifles with tubular magazines (check the data stamp on the barrel) or single shot rifles.
BTW~I'm no fan of .22WMR. More punch for close-in shooting than .22lr, but the same noise as .17 HMR with less accuracy/distance. This is anecdotal advice, based on 2+ decades of .22lr shooting, and one season of .17 HMR!
Compared to airguns~similar to some, louder than most. Spring-piston (break-barrel) air rifles are very quiet, and available at over 500fps (PAL required). The good ones are expensive, and require airgun-rated scopes. PCP, or any CO2/pneumatic air guns go off with quite a "crack" sound and yes...some high-power PCP guns (again, PAL req.) are comparable to the sound made by CB longs..dare I say, sometimes louder. SO, for the money...assuming you've done your homework on discharge laws in your area, I'd say a .22lr is your best bet. It'll also be cheaper to buy/scope than high-powered air guns. Make sure the gun is chambered for .22 lr and .22 long, or you may be forced to load them one at a time. Look for rifles with tubular magazines (check the data stamp on the barrel) or single shot rifles.
BTW~I'm no fan of .22WMR. More punch for close-in shooting than .22lr, but the same noise as .17 HMR with less accuracy/distance. This is anecdotal advice, based on 2+ decades of .22lr shooting, and one season of .17 HMR!