While I assume that the .308 will be at or near the top of the list, I was curious what most here suggest for calibers best suited (or still having acceptable ballistics) for barrel lengths between 16.5-20" might be? This will be a hunting rifle used mostly here in Texas for everything from whitetail to antelope and even aoudad. I am interested in these shorter barrel lengths because I plan to run a TBAC Ultra7 on the end and I don't want a freaking light saber of gun since it'll see some occasional use in the blind and tree stands. I know I will give up velocity and energy with most calibers when going shorter but I don't foresee this rifle getting use beyond 400-500 yards max. Let me hear your thoughts and suggestions.