The barrel has got a slight bend in it, Not uncommon.
All you have to do is rotate it like you have done.
It's referred to as shooting the barrel round, so the twist is in the vertical plane.
You will need to re check all your aim points if you want to be precise,as it may of altered your trajectory slightly.
Let your shooting do the talking.
It's not the aim and release that decided the shot, it's the preparations.