>>1720574308 seems like the caliber you need, lots of different bullet weights are available to suit your needs. I have a Ruger American in 308 and I like it. You can also get a CZ or a Tikka but those might be out of your price range. If you dig lever guns a 30-30 would probably do the job too if you spent some time at the range learning how to shoot/eventually reaching out to hit a 8 or 6 inch gong at 250 yards. AFAIK 30-30 is similar ballistically to 7.62x39 which is regarded as a good for both of the animals you listed, but costs more per round. Best of luck, I'll watch the thread if you want to ask more questions
