I'm not certain I'd try to crank the speed on an autloader unless I was sure the guts could take the repeated beating. I've never run a bar and am sure they're beefier than the rems, but this is something I think might be best addressed by the manufacturer?Assuming I am loading for maximum safe muzzle velocity, what is more reliable in these autoloaders -- heavy (210 gr) or light (168 gr) bullets?