I've got an old pre model 28 4" Patrolman in 357 magnum. It's beat to crap and has been refinished to chrome before it came to me. The finish is flaking off in many places. I was wondering, what would it be difficult to change the chambering to say 45 acp, 44 Special/44 Mag, or 45 colt?  I'm assuming I'd have to replace the cylinder and the barrel. I'm guessing there will be a difference in the thread pitch for the barrel. Any guesses how much or if this is even possible? Probably cheaper to just buy a 625 in 45 ACP........hmmm.

Just guessing, but I would say you are probably right about just buying a 625 would be cheaper.

There were several wheel-gun smiths back in the day that did what you want to do.  Probably still a few, but I bet they are very busy.  It would take a lot of time/$$$ to get what you want.

With enough patience and money, you can do damn near anything with old guns.

Refinishing it in its current form would be money reasonably spent.

Buy a different gun because you want THAT GUN.

Don't throw big money at this gun just because you don't like it in its current form. You probably still won't be happy with it.

The current gun has its greatest value in the hands of someone who can do all the work himself. Sell it to that guy for what its worth.

In the old days when labor was cheaper than materials, a lot of very artistic well executed caliber conversions were done on N frames.

These days, the labor cost for a well executed conversion to say 45 colt will easily exceed the cost of buying a different gun