POI questions

[Pieter Willem Vorster]

I hope I am posting this thread in the correct place.

Can somebody explain to me why the POI of my .308 is different with and without a silencer. I zeroed the rifle at 100 meters with the silencer, but by removing the silencer the POI is 3" to the left and 1" high.
Has it something to do with the harmonics of the barrel?

Regards
Pieter W.V.

 

[cowboy]

Has it something to do with the harmonics of the barrel?

Pieter W.V.

More than likely it has everything to do with harmonics.

 

[Pieter Willem Vorster]

On the other hand, there is no difference in POI with or without a silencer on my 7mm.
Why?