Yeah those things are badass!They also make a 50BMG version.He's wrong about having a gunsmith make barrels,they have a barrel extension like an AR that the bolt locks into.To have new barrels made would require a gun builder that could manufacture the extentions to fit to any barrels you might want.It's doable just expensive.
On another note, Im an idiot. I thought this was a semi auto, then I get to looking around and theres already a thread on this rifle in the bolt action section.