Well, kind of, sort of - - -
One of the questions asked was - -
Is it possible to fire .45 ACP cartridges in a Smith 625 that is chambered for .45 Long Colt?
The answer is not a categoric "No." It is technically possible, just highly unsatisfactory. A .45 ACP cartridge will go into a .45 Colt chamber, but lacking a rim or sufficient length to touch the end of the chamber, it will slide in too far.
If the ACP cartridge is chambered, the cylinder closed, and the muzzle pointed upward, the cartridge will slide rearward and rest against the breech. If trigger is pulled in this position, the firing pin would strike the primer and (usually, at least) fire the cartridge. The weight of the loaded round would offer sufficient resistance to make it work.
I don't know why anyone would WANT to do such a thing [noise making??), but it is possible. Actually, one could probably carefully bring the barrel down to horizontal and, if the round didn't slide forward, it MIGHT fire. No real weight holding it rearward. At very best, ignition would be uneven from shot to shot.
This is all very silly, of course. The NO answer is close enough to correct.
Best,
Johnny