7.62×38mmR


7.62×38mmR is an ammunition cartridge designed for use in the Russian Nagant M1895 revolver.
A small number of experimental submachine guns, designed by Fedor Tokarev, were also produced in a 7.62 mm Nagant chambering. None, however, were accepted into Soviet service.

Background

Designed by Léon Nagant in 1894 for his gas-seal revolver, and adopted the next year by the Russians to replace the .44 [S&W Russian] cartridge, the 7.62×38R cartridge mouth expands when fired, forming a gas seal to improve muzzle velocity by preventing gas leaks from the gaps between the barrel and cylinder.
Reportedly, Tsar Nicholas II took an interest in the 7.62×38R cartridge as he felt that a cartridge loaded with smokeless powder would make soldiers firing positions less conspicuous than the old black powder.44 S&W Russian cartridge.

Description

The cartridge uses a Full Metal Jacketed bullet seated below the mouth of the cartridge case which is crimped above the bullet. The case is rimmed and the mouth of the cartridge is designed to enter the rear end of the barrel. According to Ness and Williams, the shape of the cartridge mouth varies between manufacturers. Russian military loads had a lead core and a nickel jacket.
The Nagant 1895 revolver gas seal involves moving the cylinder forwards, so that the chamber about to be fired enclosed the rear part of the barrel and the mouth of the cartridge actually entered the barrel. Upon firing, the mouth of the cartridge expands to form a 'forcing cone' completing the gas seal. According to Hogg, the gas seal provides an estimated, while the Shooting Illustrated magazine estimated an increase of.
The 7.62×38mmR bullet performs relatively well for a .30 caliber round. Fired from the M1895 barrel, the bullet can penetrate of white pine boards at a distance. In comparison to the .44 S&W Russian, the 7.62×38mmR is lighter, with greater speed and penetration but less stopping power.
Cartridge performance largely varies between sources: According to Hogg, the M1895 fired a 108-grain bullet at 305 m/s, giving a muzzle energy of 325 Joules. Ness and Williams give the following figures: a 108-grain bullet propelled at, giving a muzzle energy of 284 J. Thompson mentions that some sources give a muzzle velocity of while others give a muzzle velocity of ; Reportedly, Pieper produced loads that propelled a 108-grain FMJ bullet at while Russian military loads had more propellant, driving the 108-grain FMJ bullet at.
Modern loadings from Fiocchi have a muzzle velocity of, allowing its use in older revolvers. According to Ness and Williams, Fiocchi loadings propel a 97-grain jacketed cylindro-conoidal bullet at. Prvi Partizan loadings have a 98-grain bullet and a muzzle velocity of, giving an energy of 160 J.
As of 2006, large numbers of M1895 revolvers remained in reserve or in paramilitary hands, while some gas-seal target revolvers are still manufactured by Russia and the Czech Republic. Thousands of Soviet revolvers and millions of rounds of ammunition were exported from former Warsaw Pact countries to the United States during the early 2000s.

Handloading

Many users of this caliber handload their own ammunition. The proper brass cases are also expensive and difficult to come by. Handloaders have had success using dies for the.32-20 Winchester and .30 Carbine to handload the rounds. 32-20 Winchester brass cases are inexpensive, readily available, and can be reformed and used safely in guns chambered for 7.62×38R, but the resulting cartridges are too short to achieve the gas seal. Cut down. 223 Remington brass reformed in 30 carbine dies can be utilized to load for the Nagant also. These will achieve the gas seal, but the case rims will be undersized.
Three other cartridges, the .32 S&W, .[32 S&W Long], and .32 H&R Magnum, will also generally chamber and fire in the revolver, but will not achieve the gas seal. The case head of the.32 S&W/H&R is about the same size as the case diameter of the Nagant cartridge, so the case head will sometimes actually end up moving into the chamber, thus preventing an adequate primer strike. Due to the dimensional differences between these cartridges and the original 7.62×38mmR cartridge, this practice is done at the shooter's own risk. The.32 H&R Magnum in particular develops much higher pressures than the 7.62 Nagant or either of the.32 S&W cartridges, which are both late 19th century developments. The most common anomaly when firing these cartridges is the bulging cases.