Best scope for HW30 targets @ 25 yards?

[Kingpin]

Picked up some rings for the dovetail base cut into the rifle's receiver. Not sure what I'm doing wrong but I cannot get the rings to bite and hold onto the dovetail. 

 

[bambuino]

Try flip spin the clamping plate over as yours may be cut for 3/8" and 11mm dovetails. Hope that works for you.