That's a tough choice between the 480 ad the 500 JRH. I have a 480 and 500 Linebaugh and like both of them. The 480 is bit easier to shoot on the top end but I don't run either up there very often. My current carry load in the 480 is a 400 grain SWC over enough 2400 to get to 1050-1100 fps. The 500 is a fairly recent addition and I haven't settled on a favorite load yet but have molds for a 440 SWC, 500 grain WLN and and 525 grain WFN (M-P mold that can do HP or solid bullets).
The 500 JRH can match the 500LB in bullet weights. If you want to go big, the JRH has a lot to offer. It can go mild to wild just like the 500LB. A 525 grain at 1000 fps will be very shootable and should penetrate the full length of most NA big game. The 440-450 grain bullets will give you a little more velocity (1100-1200) for the same level of recoil.
Buffalo bore is the only supplier of brass I know of but as you know, you can cut down readily available 500 S&W. I'm not sure but I think BFR will build a 500 Linebaugh in the same model as the JRH and brass is readily available for it.
Of course there are no flies on the 480. I love mine. I really hadn't considered one until I bought a bunch of brass really cheap thinking I'd turn it at the next gun show for little profit. It wasn't more than a couple weeks later I found a Bisley at Cabelas with a huge scratch and dent discount. It had a little swirl near the muzzle that hadn't been polished out and they discounted it heavily. I have a few molds for it, at 380 WFNGC, 400 grain SWC, Lee 400 grain FP, 420 grain M-P HP/solid, and an LBT 420 WLN.
I cannot speak personally to the performance of the 480 or 500's on game but their records are well established. My big game kills with a handgun are limited to a cougar and a whitetail doe with a 41 magnum. I can say both the 480 and the 500LB lend a sense of comfort when I am afield here in Alaska.
If I was starting all over again and wanted one big bore revolver and needed to keep the cost down, the Ruger Bisley 480 would be my choice. Going semi-custom it would be either a 500 JRH or LB in the BFR. Full custom would be a Linebaugh, Huntington, Bowen or Clements Bisley in 500 LB.
