The only revolver that I was aware of that was made in large numbers that could be effectively silenced was the M1895 Nagant. It uses a special cartridge where the projectile is recessed within the brass and a mechanism where the cylinder is moved forward when firing which forms a “gas seal”. Other revolvers allow a significant amount of gasses and noise to escape from the firing chamber.
The Vietnamese modified significant numbers of these for use in underground bunkers and the KGB used them for political assassinations. I have several of them but of course no silencers. The original Nagant brass is a little hard to find so I usually use Starline 32/20 brass using special dies to form it to fit the Nagant revolver. It forms no gas seal but works great.
First video shows how effective a silencer is on the Nagant revolver. Second video shows reloading process using Starline 32-20 brass.
https://youtu.be/UKoCIeqVHIY?t=197
“...First video shows how effective a silencer is on the Nagant revolver....”
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Damn, I don’t know if was some trick they did with the audio, but that sound suppression was the best I’ve ever heard. Admittedly, I only have personal experience with a handful of suppressed weapons... mostly ARs and one 1911 45.