Well if you're looking to trade it in the .270 and the .30-30 are proven deer killers. But all I ever had during my teens and through college was a left hand Savage 110 in .243. Using 100 gr Hornady bullets pushed by 40.5 gr of IMR4350 I killed a lot of deer with it (all but one was DRT) and quite a few groundhogs. To this day even though there are better cartridges out there I wouldn't hesitate to use the .243 on deer. As far as factory ammo goes I probably use a 100 gr load by Federal. I think it just better ammo than Rem or Win.