Best left to a gunsmith.
If it's a modern revolver, you activate the cylinder release, open the cylinder, and push the ejector rod.
Nice revolver
left side of revolver there is a small latch just behind the cylinder. pull the latch to the rear at the same time open cylinder
cylinder stop drag
Revolvers hold cartridges in a cylinder. When the revolver is operated, the cylinder turns (revolves) to align a cartridge with the barrel. Originally called a Revolving Pistol, shortened to revolver.
holster
Well, a revolver is a type of pistol (although revolving rifles have been made) which used a rotating cylinder to hold the ammuniton, and a firearm is considered loaded when there is live ammunition in the chamber and/or feeding device (such as a magazine or cylinder), so a loaded revolver would simply be a revolver which had live rounds in the cylinder, and was ready to be fired.
The cylinder lock and cylidner rod.
A revolver is a type of pistol that the cartridges are in a chamber in a cylinder. The cylinder revolves in the gun (hence 'revolver') bringing each successive chamber in alignment with the barrel. A revolver could have five chambers, it could have ten. The most common would be five or six.
cylinder
Frame, barrel and cylinder
The difference is that a pistol has a magazine and a revolver has a rotating cylinder that has individual chambers to shoot