I have a nice German made- don't recall the name- double in 8x57jr, with the original claw mt scope. It will regulate fine with both the iron sights and the scope with the same load! Likely this is not the norm, but certainly is possible! BTW the load I am using, due to the difficulty of getting 220 gr bullets, is a lighter bullet at a reduced velocity. This may or may not have any bearing on the situation, but indicates you may need to work on loads?
Enjoy! Doug