I've shot the 308 from hell to breakfast and needn't guess.

Does loading the 308 down make it more "effective" on Game? Hell,all you gotta do is add more up,hold more wind,hit Critters softer and save on powder.

Though of course,that ain't how the ball bounces,because such things do factor terminal affects...which is how stuff dies reliably dead.

All of which are a great series of unknowns to you,due to your being fraught to suffer your very own "experience". Tough row to hoe,for sure.