BUT IIRC this link is not comparing reloads to reloads, the AR can handle higher pressures than what most X39 is loaded to by factories IIRC.
Regardless to me the 2 are extremely similar to each other in the end.

We can keep Larry Root and all his idiotic blabber and user names on here, but we can't get Ralph back..... Whiskey Tango Foxtrot, over....