Well I had some issues with my 500 and I thought it was me or bullet loads.I found my problem and are ya'll ready for this, it was the level I used to level the scope on the 500. So after all the head pounding I did for something so small. I can't find my notes on mounting the scope on my 500 so do you put rings forward on the rail gap or the the back.Im using Warne Maxima Steel Rings. The the recoil key don't fit tight on rail and I know it makes a difference. Thanks

Under recoil the gun moves back - scope moves forward. Push the rings forward when you tighten them. I hope this helps.

Thanks

+1 Almost all of my scoped guns have those rings. I like to add a little blue lock-tite between the base/barrel-receiver, key/base slot, and all mounting screws. I've never seen a key fit tightly in the slot, and on one particular set-up (a MkII with a Weigand base), the keys were a tad long which prevented the rings from snugging down tight to the rail. Looked fine on the bench and at the range. But on a squirrel hunt thereafter, I missed one, hit one, and then missed 2 more, before I finally figured out the very slight movement and corrected it with a little file work to the keys, then re-mount/re-sight scope.