A little late since I already paid for the barrel.
David Tubb's 33XC was pushing the WFL 285gr at 3200 fps without any pressure signs(supersonic just past 2600 yards). Plus, with the die set you get, it will do 37XC and 41XC. The 37XC is pushing a 400gr Warner FL at 2900fps (33 inch barrel). The
Warner 400gr G7= .552 vs. Barrett's 416 452gr at 0.42. If you believe the Warner BC, which they claim is Doppler verified, the Warner 400 is supersonic just past 2600 yards (1000ft-lbs at 2840yd) and the Barrett 416 past 2300 (1000ft-lbs at 2800yds). Their energy is about equal at a mile. And you don't have the .50 cal cartridge to deal with reloading. I believe Tubb makes a pretty compelling argument for tons of options to get into ELR shooting.
I definitely would consider a single stage. I have tons of 556 ammo and really don't think I have the patience to load 1000's of rounds for something you can buy cheap, or used to could have anyway.