Just in case anyone on here is unsure if the rear sight on the Baikal Mak is adjustable, it is...

I supported the gun on soft wood with a tea towel underneath, got my partner to hold it down using the pistol grip then tapped the edge of the sight using a bolt and hammer, second tap and it lined up in the middle nicely (sight was too far to the right, so gun shot about 3 inches to the right as it came straight out of the box).

Hopefully this will be of help to someone.

Ed