Aren’t most standard velocity 40 gr .22 LR subsonic out of a <5” barrel?
Almost all .22 LR cartridges average subsonic out of a less than 5 inch barrel.
There are only a few .22 LR cartridges which are reliably supersonic out of a less than 5 inch barrel.
There are a fair number of .22 LR cartridges which have a significant percentage of shots which give supersonic signatures when fired from a five inch barrel.