# 9×39mm

The 9×39mm is a Soviet rifle cartridge. The cartridge yields increased performance in shorter barrels and effective subsonic performance.

## History and design

The 9×39 is based on the Soviet 7.62×39mm case but with the neck expanded to fit a 9.2mm bullet. The final design was completed by N. Zabelin, L. Dvoryaninova, and Y. Frolov of the TsNIITochMash in the 1980s. The intent was to create a more stealthy cartridge for suppressed firearms used by Spetsnaz and other special troops that had more power, range, and penetration than 7.62 US subsonic rounds tested at the time.
The subsonic round is originally designed to have an optimistic effective lethal range of 400 to 530 meters and a maximum penetration of up to 10 mm of steel. Like the 5.45×39mm cartridge, the 9×39mm SP-5 features an air pocket in the tip, which increases its tendency to yaw or "keyhole" upon impact, thus increasing soft tissue damage in human targets. The armor-piercing SP-6 cartridge is more effective against light armor, vehicles, or light barrier targets.
Commercial Wolf and Tula brand Ammunition that was being imported into the United States was subsequently banned on September 7, 2021 by then president Joseph Biden as part of sanctions against Russia for poisoning of Aleksey Navalny.
While the 9×39 is very popular in several European countries, many of which had previously been under the control of the USSR, it was only introduced in the United States in late 2018.
Since there are many users in the U.S. that had adopted the 9×39 round prior to the import ban, were forced to reload their own ammunition. However, there are multiple companies worldwide who make 9.3mm (.366") Mauser bullets which are suitable for reloading in the 9×39, including Hornady, Barnes, Nosler, Prvi Partizan, Lapua, and others.
Roswell Manufacturing has developed and tested what they are calling the 9x39US though it has different specs than the original 9x39 Russian.
During development, Roswell Manufacturing identified significant inconsistencies in existing 9x39mm ammunition and tooling specifications, with some tooling even mislabeled. As a result, Roswell opted for a combination of standards.

## Variants

| Cartridge | SP-5(7N8) | SP-5UZ | SP-6(7N9) | SP-6UCh | PAB-9 | SPP | BP(7N12) |
| Type | Sniper | Test (increased charge) | Armor-piercing | Training | Armor-piercing | Sniper (increased penetration) | Armor-piercing |
| Bullet weight [g] | Up to 16.8 | | About 16 | | Up to 17.3 | | |
| Muzzle velocity [m/s] | 280–320 | | 280–290 | | 280–305 | 280-320 | 280-310 |
| Muzzle energy [J] | 658-860 | | | | 678-886 | | |
| Maximum penetration | | | Up to 8 mm of steel | | Up to 8 mm of steel | | |
SP-5 (7N8) – The SP-5 (СП-5) (SP: Spetsialnyj Patron; "special cartridge") was developed by Nikolai Zabelin. It is a conventional lead core FMJ bullet, developed for accuracy.
SP-5UZ – The SP-5UZ (СП5-УЗ) is an SP-5 variant with an increased charge intended for a factory-specific strength testing of the weapons.
SP-6 (7N9) – The SP-6 (СП-6) was developed by Yuri Frolov. It has a hardened metal armor-piercing core. It can penetrate 2 mm (0.079 in) of steel at 500 meters or 6 mm (0.24 in) of steel, 2.8 mm (0.11 in) of titanium or 30 layers of Kevlar at 200 meters. At 100 meters it can penetrate 8 mm (0.31 in) of steel or GOST 3 rated body armor, while retaining enough power to inflict damage to a soft target behind it.
SP-6UCh – The SP-6Uch (СП-6Уч) is an SP-6 variant intended for training.
PAB-9 (7N12) – The SP-6's bullet is expensive to manufacture, so an attempt was made to make a lower-cost version of the cartridge. The PAB-9 (ПАБ-9) used a stamped rather than machined steel core. It sacrificed too much performance to be usable. As of 2011, its usage by Russian troops is prohibited.
SPP – The SPP (СПП) (SPP: Snaiperskiy, Povishennaya Probivaemost; "sniper – increased penetration") is a sniper round with increased penetration.
BP – The BP (БП) (BP: Broneboinaya Pulya; "armor-piercing bullet") is an armor-piercing round. Three modernizations of PAB-9 were created under the designation of BP to remedy its unusable performance.

## Weapons

* 9A-91
* AK-9
* AS "Val"
* OTs-12 "Tiss"
* OTs-14-4A "Groza"
* SR-3, SR-3M "Vikhr"
* VSK-94
* VSS Vintorez
* AMB-17