Leupold double dove tail. That is all I use anymore on my TC’s. They are doing just fine on my 45-70 and my 375 H&H. When you want to start handloading for it, call TC. The tech’s will go out of there way to help you an they have been handloading a long time! 1800-243-4570 ext 752. The complete reloaders guide for the Contender is also VERY good.