Leupold has QRW (Quick Release Weaver) rings that will mate right up with your Weaver bases. Do not confuse QRW, with QR rings, they are two different systems that Leupold has. Warne also sells a quick release ring, for Weaver type bases. You could also use Weaver Top Mount rings. These are detatchable from the Weaver bases. I personally use both Leupold QRW, and Warne quick release on my inlines, and centerfires. Check Midsouth Shooters Supply. I believe they sell these rings, and the correct Weaver two piece bases for your Thunderhawk.