I tested my .22 LR silencer for point of impact shift on my Ruger 10/22 rifle some 10 years ago. I vaguely remember that the result was that the point of impact shift seemed to be there, but very minor. Only one minute of angle --which was less then the variation I would get when switching brands of ammo. And I found that the silencer didn't impact accuracy at all. I eventually replaced my 18" threaded Ruger barrel with a 22" Green Mtn. threaded barrel. Yesterday I tested the 10/22 again. I used CCI Subsonic HP ammo. 5 rounds prone at 50 yards, suppressor on muzzle. Got a 2.5" group. Took the can off, screwed on the M16A2 bird cage I use instead of a thread protector, and shot a sub-inch group. Same position, prone. Same distance, 50 yds. There wasn't any noticeable point of impact shift. Both groups were a couple inches high and about an inch and a half left of center. That could be due to the type of ammo I was using and the wind conditions. Also I think my rifle has been sighted-in for 100 yards so it should be high if I'm firing at 50.