A big issue here is the lead ban. California has more gun owners than any other state in the Union and the shooting sports, including Cowboy Action shooting is huge here. All of these arms use lead, you cannot fire anything but lead bullets from an old time firearm. This will mean millions of dollars revenue lost in California and many native born Californians like me moving to Nevada. Thank God the border is only 20 miles away.
I imagine there are other things you could fire from them. None of which would give the same performance, and all of which would cost more, perhaps a lot more.
But if think the gun grabbers give a hoot about that, or loss of state revenue, you are sadly mistaken. They'll just find something else to tax.
Waterfowl hunters faced a lead ban long ago. Bismuth, steel (that's out of course for you CAS guns), and other materials have been substituted. The higher cost is not that big a deal for waterfowlers, since no one actually expends all that much ammo when hunting... except maybe dove hunters. :) But guys shooting paper, steel or even pitch ("clay" targets), put lots and lots of rounds downrange, to the point where the cost of ammo is a significant portion of their total costs. But again, the gun grabbers don't care about "legitimate sporting purposes", no matter how much they bleat about it when trying to pull the wool over the sheeple's eyes.
Of course they'll extend it soon to hunting squirrels, rabbits, and other small animals, when it's discovered that the Condor, and other carrion birds, eat even more of those.
Even now, the technical challenge to this is pretty high, since they can't do like the waterfowl hunters and use steel, that would be an "armor piercing" round, as would most any metal much harder than lead. Bismuth with a plastic coating? Lead free ceramics? Deplete Uranium with a lighter metal core or cladding? Of course it has to be soft enough on the outside to "grab" the rifling, and not so hard as to cause excessive wear on it. Big challenge.
Anyone have any information on what is being proposed for big game and coyote hunting in CA? Of course the people who enacted the ban don't worry about little things like that.