I have a set of Warne Premier bases matched up to a pair of Brownells 7.3 rings. The dovetail parts mate up just fine (as Brownells says they will), but I notice that the top of the scope base does not contact the flat between the dovetails on the rings (contact is only made on the dovetailed part of the rings). The base has a grove like a picatinny rail that mates up to a cross beam on the rings.

Never seen where the scope ring doesn't contact on all side, curious if this will be an issue?

If anyone is curious, I had tried a few sets of Warne Premier rings, but they kept coming loose under the recoil (9.3x62). All were QD versions, the 7.3's mentioned above are fixed, tightened using a torque wrench.

Properly matched rings and bases should see the the underside flats of the ring base pulled down hard to the top of the base as the dovetail components of rings are tightened. If there is a gap then they are mismatched.
I have only ever used original Weaver bases and rings, the ones with the steel band which is tightened on one side, can be a pain to get the scope crosshair horizontal but once it is the scope never moves. The rings pulled down solid on the bases and have full support.

To many other poorly designed and fitting rings and bases out there to be bothered with (a few posts on AR showing broken Warnes).

Back to brownells they go.