243 or 308?

Thanks guys I really don't know a whole lot about the science of shooting and ballistics but from what I research I can't decide on what to choose. I'm sold on the 100atr, I just need some input on what would give the best accuracy at 100+ yards for hunting between 243 or 308, plain and simple, please give me your opinions

If you had to choose between the two rounds with cheap ammo to shoot a longer distance as accurate as possible, which would u choose?

to work my way up to shooting At least 200 or 300 yards, what would be the easiest or best choice between the two rounds?? I know that the 243 has flatter trajectory, but I didn't know if there are other factors that could benefit 308? I really don't know. Please educate me. Thanks

And yes sus scrofa i like where you are coming from, but I'm just in need of an easy shooter at a longer range than my other guns are cape able of for deer and coyote hunting, and I just want a gun that will give me the most accurate shot possible for cheap, and I'm not sure of the factors that each of these rounds have that will effect the accuracy

Thanks a ton everyone, its all very helpful. I think I have my mind made up now

Thanks everyone, I just picked up the night train in 308 and I love it. I can't wait to see what I'm capable of doing with it

Thanks everyone