My crown did that just removing and reinstalling the liner to clean it. That said, I'm not sure if it's normal - mine has issues and is in for warranty work now so will see what happens when I get it back.
Yes it’s normal. Even the best barrels when indexing will scribe a circle quite large at 20 metres.
The liner in the x barrel can be indexed at 6 or 12 o’clsock for some marginal increase in accuracy. Then you need to mark it with a dot of paint or similar so it goes back in the barrel in the same position.
It means the barrel or the bore is bent slightly ? if it is, I will take advantage of it by selecting the position at which the elevation setting of the scope is the furthest away from it's adjustment limit.