If you are looking for a quiet 22 rimfire round, consider the Winchester SUPER-X CB-Match round. Â Winchester Ammunition introduced the .22 Long rimfire cartridge in 2008. Â The round is designed for high accuracy and very low noise.
The SUPER-X CB-match .22 Long round pushes a 29 grain bullet at a relatively slow 770 fps from a 24″ barrel. Â From a 6″ barrel, Winchester states the muzzle velocity is a paltry 575 fps. Â Expect even less velocity from a handgun like the Walther P22 (3.4″ barrel) or Ruger SR22 (3.5″ barrel.)
This round matched to a gun with a sound suppressor, and this should be a very quiet shooting round.
I would expect that this round would be reliable in only bolt-action and single-shot firearms. Running it in a semi-auto pistol or rifle may not work well, as the load probably doesn’t generate enough force to reliably operate the gun’s action. Of course, I could be wrong, and if anyone has any luck running this in a semi-auto gun, please sound off in the comments section below.