This has been discussed numerous times on several sites I visit and it has been proven that the issue exists. However, how much it actually effects your accuracy is a matter of never ending debate. For guys who shoot for extreme accuracy, any amount that can be accounted for is too much and shooting sub sonic eliminates at least one variable. As far as HV ammo I used to shoot a lot of Winchester Power Points and other ammo in that velocity realm - approx. 1400 fps- and had good results with it for hunting ammo and on paper it was very good, but not what I would call target ammo. Since they moved the manufacture of Win Power Points from Australia to the US, the accuracy isn't what it used to be.
Unless you are a bench rest shooter this may or may not effect you which is why so many guys who say they have shot a ton of .22 ammo in their lifetime call BS on this claim. For hunting accuracy you can probably be minute of squirrel head with most ammo still...
