You would have no problem taking a deer with the 300 Whisper. It is one of the best all around cart. out there. You can push a 125 gr. Nos. Bil. tip over 2400 fps with 22 gr's of H110, or about 2100 fps with a 150 gr. and about 18 gr's of H110. It will give you aprox. the same power as the 7.62x39mm (AK 47 rnd) on the high end, as well as top notch performance in the sub sonic area's. It is one of the most versital rounds out there, and if you could only have one bullet it would be a hard one to beat. Another one to look at is the 338 Whisper, same type of set up, but bigger. You can get it in short or long barrels, bolt act., or an AR 10 with a 338 Whisper upper for it from SSK and shoot anywhere from sub sonic rnd's with 300 grn heads, to very hot loads with 200 grn bil tip heads. If this still won't fit the bill, take a look at the 510 Whisper.... WOW! 600+ yards in sub sonic! JD Jones has made a lot of good rounds in his time, but the Whisper's really are worth a look.I know a few people with Whisper's and everyone of them put the Whisper's at the top of their list.