7.62×39mm

Lore & Background

On July 15, 1943, the Technical Council of the People's Commissariat for Armaments met to discuss introducing a Soviet intermediate cartridge. The job of designing it was assigned to a committee led by chief designer N.M. Elizarov, assisted by P.V. Ryazanov, B.V. Semin, and I.T. Melnikov. About 314 cartridge designs were considered theoretically before eight were physically constructed and tested. The first variant, with a 41 mm case length, was adopted in December 1943 and given the GRAU index 57-N-231. After further refinements, a pilot production series began in March 1944.

Starting in 1947, the cartridge was tweaked by the Ulyanovsk Machine Building Plant to improve accuracy and penetration. A boat tail was added, the ogival head lengthened, and the case shortened to 38.7 mm, resulting in the 7.62×39 designation. The new bullet, designated 7.62 PS, had a lead core wrapped in low-carbon steel. The 7.62×39 cartridge with the PS bullet overcame all objections of the GAU in mid-1947 and was ordered into series production as 57-N-231S. Field tests of the round and the new prototype AK-47 were carried out from December 16, 1947, to January 11, 1948.

In the mid-1950s, Elizarov's team developed a special subsonic bullet, adopted in 1962 as 7.62 US. After 1989, regular PS bullets began to be manufactured with a heat-treated steel core, improving penetration. A normal-velocity bullet called BP, made of tool steel, was adopted in 2002 as 7.62 BP (GRAU 7N23). The BP bullet is claimed to achieve over three times the penetration of the PS bullet.

Reader's Guide

The 7.62×39 mm cartridge is significant as the standard Soviet infantry round from the late 1940s through the 1970s, and it remains in widespread use globally. Its development was a direct response to the need for an intermediate cartridge that could be used in a range of infantry weapons, including semi-automatic carbines, selective-fire rifles, and light machine guns. The cartridge's design was refined over several years, with the final PS bullet variant achieving improved accuracy and penetration. The 7.62×39 is most famous for its association with the AK-47 and its derivatives, which became the world's most widespread military-pattern rifles. The cartridge's tapered case contributes to the distinctive curved magazines of AK-pattern rifles. Although partly replaced by the 5.45×39mm in Soviet service, the 7.62×39 remains in use with modern Russian rifles like the AK-15 and continues to be a common chambering for newly developed rifles. Its legacy is tied to the global proliferation of Kalashnikov-pattern weapons, making it one of the most widely used cartridges in military history.

Did You Know?

• The initial 7.62×41 variant had a case length of 41 mm and a bullet with a lead core, lacking a boat tail.
• The PS bullet's steel core accounted for about 50% of the core volume, and the 'S' initially stood for 'surrogate' (суррогатированная).
• The subsonic 7.62 US bullet is 33.62 mm long and 12.5 g, with a larger maximum diameter of 7.94 mm compared to 7.91 mm for other bullets.
• The BP bullet, adopted in 2002, is claimed to achieve over three times the penetration of the PS bullet and can defeat the Russian 6B5 vest at distances below 250 meters.

From Council Table to Combat: The Birth of an Intermediate Round

On July 15, 1943, the Technical Council of the People's Commissariat for Armaments convened to make a decision that would reshape Soviet infantry firepower: the adoption of a new intermediate cartridge. Planners envisioned this round serving an entire family of weapons—a semi-automatic carbine, a select-fire rifle (what we now call an assault rifle), and a light machine gun. The design task fell to a committee chaired by chief designer N.M. Elizarov, with P.V. Ryazanov, B.V. Semin, and I.T. Melnikov as his assistants. Elizarov worked in close consultation with prominent weapons designers including Fedorov, Tokarev, Simonov, and Shpagin. The process was exhaustive: roughly 314 cartridge concepts were evaluated on paper before the field was narrowed to just eight models that were actually manufactured and range-tested. The bulk of this engineering effort was carried out at OKB-44, a laboratory that would later be renamed NII-44, merged into NII-61, and ultimately folded into TsNIITochMash in 1966. The very first variant cleared range trials in December 1943 and received the GRAU index 57-N-231, though its case measured 41 mm, earning it the informal label 7.62×41.

The Boat Tail Controversy and the PS Bullet

The original 1943 bullet was a blunt 22.8 mm projectile with a pure lead core and no boat tail, its widest point reached just 13.01 mm from the tip. When the Ulyanovsk Machine Building Plant took over refinements in 1947, a key assumption was overturned. Soviet designers had initially skipped the boat tail, reasoning it would only matter once the bullet dropped below the speed of sound at longer ranges. Range data proved otherwise: the tapered rear section sharpened accuracy even while the projectile was still supersonic. The revised bullet gained a boat tail and a lengthened ogival nose, pushing the point of maximum radius out to roughly 15.95 mm and stretching overall length to 26.8 mm. To keep the cartridge's total length constant, the case sleeve was trimmed to 38.7 mm—the origin of the familiar 7.62×39 designation. The core was reworked: lead was now wrapped in low-carbon steel, driven largely by the desire to repurpose 7.62×25mm Tokarev production lines. The steel made up about half the core's volume. The "PS" in the new 7.62 PS nomenclature originally meant "surrogate," though it was later reinterpreted as standing for "steel." The improved round satisfied the General Armaments Directorate in mid-1947, received the index 57-N-231S, and entered series production.

A Cartridge That Outlived an Empire

The 7.62×39 mm—also known as 7.62 Soviet and, in earlier Western usage, .30 Russian Short—is a rimless, bottlenecked intermediate cartridge of Soviet origin whose global footprint is inseparable from the weapons that fire it. The AK-47, designed in the immediate aftermath of World War II and later refined into the AKM after early sheet-metal receiver production ran into difficulties, became the most widely deployed military-pattern rifle on Earth. Alongside the SKS semi-automatic rifle and the RPD and RPK light machine guns, these platforms carried the round into service after service. The cartridge held its position as the Soviet standard issue until the 1970s, when the 5.45×39mm round and the AK-74 rifle began to supplant it. Yet the 7.62×39 never fully disappeared from Russian arsenals: it persists in the modernized AK-74M service rifle and the AK-12. In the 21st century it remains a common service chambering, appearing in newly developed rifles such as the AK-15. Few intermediate cartridges have achieved such a long and geographically vast operational life.

Subsonic Variants and the Evolution of the Case

Beyond the standard PS bullet, the 7.62×39 platform spawned specialized ammunition tailored for particular roles. In the mid-1950s, Elizarov's team—by then working at NII-61—developed a dedicated subsonic projectile. Adopted for service in 1962 under the designation 7.62 US (the "US" abbreviating "reduced speed") and the GRAU index 57-N-231U, this bullet was markedly longer at 33.62 mm and heavier at 12.5 grams than its supersonic counterpart. Its core architecture was fundamentally different: rather than the layered lead-and-steel construction of the PS round, the subsonic bullet's head section was made entirely of tool steel, followed by a separate lead section. It also carried a larger maximum diameter of 7.94 mm, distinguishing it from all other 7.62×39 projectiles. On the case side, the original 57-N-231S round used a bimetallic steel-and-copper shell. In the early 1960s a lacquered steel case was introduced, initially designated 57-N-231SL, before the 57-N-231 label was simply recycled to cover all steel-cased 7.62×39 Soviet ammunition regardless of construction.