I've used a 243 since 2008 and its killed a ton of deer. Its a Remington Model 798 mouser action that Remington ran a few years ago. A lot of people off this very site got the money together so i could buy the gun as a coming home present from Iraq. I have only had one deer not end up in the back of my truck and that was due to bullet selection. Even with the cheap Federal ammo I was using at the time, it killed deer on the spot most of the time.The past two years I've switched to the Hornady Superformance ammo and both deer I have shot have fell dead with out even flinching.A good bullet out of a .243 will get it done.