The development of better powders, including smokeless powders, in the 1880-1890 time frame meant that bullets could be driven faster than was possible with black powder. This being true, the same lethality could be achieved with smaller bullets moving faster instead of big bullets moving slowly.
This resulted in development of the (then) small bore rifles, like the German and French 8mm, the British .303, the American .30 (.30-40) and the like. The same thing happened in revolvers, and the old big bore 12-15mm revolvers were replaced by smaller calibers in the 7.5-9mm range. In the U.S., the .45 Single Actions (Colt and S&W) were replaced by the .38 revolver (1892). (The U.S. later returned to the .45, but that is another story.)
Actually, the Russians were rather late in adopting a small caliber revolver, mainly due to a chronic lack of money. Sweden had adopted a Nagant design in 1882, and Switzerland a similar type (though not a Nagant) in 1887. Russia adopted the Belgian designed 7.62mm Nagant revolver in 1895,, and that is the model number usually given it.
Most revolvers have a gap between the barrel and cylinder, necessary to allow the cylinder to turn, but a point at which gas escapes reducing, at least a little, the velocity of the bullet. The revolver adopted by the Russians gets around that problem by sealing the gap. The Russian revolver is not totally unique, as the sealed cylinder design was used on some civilian guns, but it was the only widespread use of the design. In the Model 1895, the cylinder is moved forward so that circular cutouts in its face fit around the end of the barrel. If this were all, the gap between the barrel and cylinder would be reduced, but would still be present.
But the Nagant cartridge has its bullet seated deeply in the cartridge case, and the case is of a length to protrude beyond the chamber into the cylinder cutout. When the cylinder moves forward, the mouth of the case is inserted into the end of the barrel, so that when the gun fires, the gap is completely sealed by the case.
This has been proven to have been an unnecessary refinement, and millions of revolvers have been made without it. But the revolver served Imperial Russia and the USSR well, in two world wars, and was not fully taken out of service until 1947.
Many writers, apparently never having actually seen one of the guns, have described them as complex, delicate and fragile. This is nonsense. It is true that the mechanism has a few more parts than other revolvers of the type, but those parts are big, rugged and gave almost no trouble. Even the long and fragile looking firing pin rarely failed.
The age of the design, though, is shown by the fact that it is a solid frame, with a loading gate on the right hand side. Case ejection is by a rod that rests in the middle of the cylinder base pin until it is pulled forward and swung to the side to act as an ejector.
Disassembly for cleaning involves swinging the ejector rod to the side and removing the base pin to remove the cylinder. The internal mechanism is exposed by unscrewing one large screw on the right side, which allows release of the side plate on the left.
The double action trigger pull is, as might be expected, quite heavy but not impossible. Single action pull is not bad and consistent with other revolvers of the period, though not as good as contemporary Colt double action revolvers.
HTH
Jim
