If only they made the Savage 24 with a .222 Remington Magnum barrel. It's such a commercial success, just this morning I saw Nosler brass available for a mere 96 cents per (sure glad I've got plenty). I can't recall the last time I saw factory ammo in that caliber on a store shelf. And that's not just because I'm old and my memory is poor.As to the reasoning of chambering the .222, it was introduced in these guns prior to the .223's success as a commercial cartridge.
For the handloader/target shooter it is a better cartridge. Longer neck for cartridge concentricity, better powder efficiency and it held benchrest records for decades. As a hunting cartridge it gives up little or nothing for power or range compared to the .223.
Reaming a decent Model 24 from .222 to .223 would completely destroy any collector value to the gun.
The only logic to the operation would be factory ammo availability. .222's were for a while almost non-existent on store shelves, but I saw two varieties on the shelf last week. Logic dissipates. Never existed for the handloader.