This is S & Ws new cartridge for the 500 frame revolver. Ammo is by CORBON. Think of it as a 454 Casull magnumized. The first factory ammo will use a 200 grain Barnes X bullet at 2300 and some change FPS from the 10″ barreled revolver. The same ammo does 2650 FPS from a 14″ SSK Encore. Recoil is very mild for such a powerful cartridge. 454 and 45 Colt ammo can be used in the same chamber.
I got over 2100 FPS with a 300 grain jacketed bullet first try in the Encore. I think there is another 1–200 FPS there with the 300 grain bullet. Barrels are now available from SSK.
Case length of the 45 Colt is 1.280″; for the 454 Casull 1.380″ and a gigantic 1.790″ for the S & W 460 Magnum,  The 45 Colt and 454 can be fired in the S & W cylinder.
The first ammo loaded by COR BON uses slightly boat tailed 200 grain BARNES X bullet.