The biggest hurdle I found while trying to scope the K31 (besides figuring out the tight throat and correct bullet and seating depth to use, etc) was actually finding the correct scope rings to use for the Swiss Products clamp on mount! I bought 3 sets of mounts before finding the correct one that actually fit the mount the best and had the most surface area actually clamped onto the mount. I originally tried 11mm Leupold Steel rings (might work in a pinch, but are technically too narrow for the 3/8" dovetail) and then purchased the Leupold 3/8" Steel rings. These rings again, while being the "correct" size for the mount, barely had any surface area holding onto the mount itself, while they would probably work, I still wanted the best attachment point I could achieve. Next I tried the Weaver "Grand Slam" Steel rings for 3/8" mount, but they again, didn't have much mounting surface area, and were a little wider than I liked. In the end it was the Steel 3/8" Burris rings (NOT their "Rings for Grooved Receiver .22", which is most likely 11mm) that worked absolutely perfect on the mount and fit the bearing surface to a "T"!
