Sort of like, "Why is insurance on a Cadillac so high??" I think part of it is that they figure if you want to shoot a round that is so large and powerful, etc, etc, you'll pay what you have to for a gun with which to shoot it. Nobody would pay a "premium", as it were, for a 38 Special or 45. Also, maybe the "status symbol" aspect of the Casull weapon raises the price somewhat. My $.02.
Very true cpt, that is what we are saying, back when I shot allot and reloaded the Casull was just coming out and still a "wildcat" he hadn't even found a cartridge mfg. yet, then he got one, shot it once in a Ruger black hawk, never shot it again. Back then everyone had to have one, but it was funny they were for sale cheap used, with low rounds shot.
Stopping power is subject to interpretation, so I won't get into that. For energy release, the cassull tends to be at least 50% more powerful, or in the below example, about 2x as powerful. I found the below on a website, I will provide a link for verification.
Chambering Bullet Velocity Energy(ft-lbs)
.480 Ruger Hornady 325-gr. XTP-MAG 1350 1313
.44 Magnum Hornady 300-gr. HP/XTP 1150 881
.45 Colt “Magnum +P” Hornady 300-gr. JSP 1300 1126
.454 Casull Hornady 300-gr. XTP-MAG 1650 1813
.475 Linebaugh Hornady 400-gr. XTP-MAG 1300 1501
NOTES: All figures are for 71/2-inch test barrels
I will also note the .454 Cassull is more powerful than the .50AE (which is NOT the same as the 500 magnum). The .50 magnum is 50% more powerful than the Cassull, at [I believe] 26-2800 feet pounds of energy (for the .50 mag).
For hunting, I use:
.454 Casull Hornady 300-gr. XTP-MAG
They have a serious kick. However, they have stopped everything in its tracks with 1 shot. I only take a shot if I know I can hit the kill zone, so that is also part of it. I will say that you'll want to keep in mind what is behind your target. On one hunt, I killed 2 hogs with 1 shot. The second hog was accidental, I did not intend to get both. But it does go to show how powerful that round is.
Another comparison of the 300gr Hornady for the Cassull is that it packs the power of a .243 rifle in a pistol.