243 will get the job done obviously, but it is a light caliber for big game. The lack of blood probably didn't have a allot to do with the caliber. I shot a big boy Sunday morning with a TC omega 250gr shockwave and blew a hole through his lung and liver you could put your fist through and he walked 5-600 yards with absolutely not one drop of blood to the point where he stopped an d piled up in a tree. Sometimes it happens but I would recommend a bigger caliber for deer.