Ammunition designed for the .22 Winchester Magnum Rimfire cartridge, loaded to propel projectiles at velocities below the speed of sound, offers distinct advantages. This specialized type typically utilizes heavier bullets than standard loads to maintain energy at lower speeds. An example would be a 45-grain projectile traveling at approximately 1050 feet per second, compared to a standard 40-grain projectile at 1900 feet per second.
Reduced velocity offers several key benefits. The lower speed minimizes the sonic crack produced by a supersonic projectile, significantly reducing noise. This makes it particularly attractive for pest control, suppressed shooting, and training where noise reduction is a priority. The heavier bullet construction often associated with these loads can also contribute to increased accuracy and terminal performance at shorter ranges. While not a recent development, the growing popularity of suppressors and increased focus on hearing protection has elevated the importance of these quieter cartridges.