Just thinking about different Vehicle guns to sit on your chest as you are driving. I make a AR pistol in 50 AE in a 9 inch barrel. Great for putting holes in things from 5 feet to 100 yards from a window.
The 338 Federal can be made in a AR10 chassis and brass is dirt cheap. To me a private citizen with a budget getting brass cheap for practice and play is a must. 50 AE brass and 308 LC brass is cheap.