AR2201
I know I forgot something to add. I was lucky enough to get one barrel set which was produced at the beginning with the fixed muzzle, the old fashioned soldered one.
So it is not adjustable, but Ziegenhahn & Sohn does a very good job on the regulation. With the discribed ammunition 2 right and 2 left will get me a group of 26mm or a little more than an inch at 100 metre with using the scope!

Robert