There are a number of superb choices, but one of the best -- and easiest to form and load for -- has to be the 30-30 AI. With a 24" barrel, you'll be in the 2550 to 2600 fps neighborhood with 150 grain bullets.
Both Varget and W748 -- among several others -- will get you there, and either the 150 grain BT or the CT-BST will afford superb terminal performance on everything from deer to hogs.
Life of the improved case is long if you don't overwork them in the sizing process, and the design helps keep trimming to an absolute minimum compared to the parent cartridge. But the 30-30 AI is far from the final word in workable cartridges.
The 7mm Bullberry, 7-30 Waters or 6.5 Bullberry IMP (aka 6.5x30-30 AI) will do the job just as well. From a 24" barrel, the 7BB will approach 2700 fps with 120s, the waters will reach 2600 fps with 140s (book loads, by the way!) while the 6.5 BB IMP will do 2550 fps with 129/130s or 2400 fps with 140s.
As long as you match the bullet to the job at hand (not to mention to the respective velocity window!), all have ample energy to do the job easily out to 300 yards. Near or far, big or small, these cartridges have served me exceptionally well. In fact, if there's a deer or hog inside 300 yards that can't be killed cleanly with one of these calibers in a Contender, then I would not be able to kill it with anything larger, either.












