If you wish to rechamber
it, the gun's worth wouldn't be affected all that much.
So it's a common pastime to rechamber
or rebarrel to different cartridges.
With factory barrels and long throats, a gunsmith can remove the barrel, set it back a thread, and rechamber
with a shorter throat.
At the same time I had him rechamber
of the cylinder of a second Dan Wesson .32 H&R to .327 Magnum.
My assumption that the sheer cost of full length barrel boring and rifling machines plus the space required to house them will not exclude requests you rechamber
a rifle remains unchanged.
If you have a Win Mag you're not content with, your most cost-effective option will be to rechamber
it to a Lott, but the .458 African route is not all that much more expensive, and it is eminently practical, easy to reload for, and there's really no question about performance.
Due to the existing cylinder length Webley could not easily rechamber
it for a longer and more powerful cartridge.
Of course, this assumes the gun was not stabbed into the object, causing the slide to partially extract and then fail to rechamber
If you decide to rechamber
to the Lott (and if you can do so--the .458 Lott requires a .375 H&H-length action), you can practice with lower-recoil .458 Win.
Unfortunately, Italians soon found the fact that there were now two separate rounds in the system to be something of a logistical poser and decided to rechamber
many of the new rifles back to 6.5mm and get rid of some of the others.
I have a Ruger 77 stainless in .280 Remington I would like to rechamber
to 280 Ackley Improved.
One traditional solution is to unscrew the barrel and cut off an inch or so of the barrel shank, then rethread and rechamber
the barrel, but so-called "fire-lapping" can also rejuvenate a worn throat.