I modified some Kelbly rings for my Hall. You need to mill off the bottom of the ring [ .025 ? .030 ? ] and then take off some metal off the ring's dovetail so it doesn't bottom out in the root of the receiver's dovetail. You need to verify this on any rimfire dovetail set up. The rings need to bear on the receiver's machined angles and not touch down in the root of the vee.