1. A-91 

Even though Soviet arms manufacturers have experimented with the bullpup design where the action is located behind the trigger group, bullpup assault rifles have seen limited production and are in service with a few select internal Russian units.

It was developed during the 1990s by KBP Instrument Design Bureau in Tula, SSSR, as an offspring of the 9A-91 firearm family.

A bullpup configuration permits a shorter overall weapon for a given barrel length. It also ensures better accuracy of fire, which is vital in urban combat situations. A-91 retains the simple gas-operated, rotating bolt action and a trigger unit design from the 9A-91.

The A-91 assault rifle, developed by the Shipunov Design Bureau, was introduced in 1990. It comes in two variants: a “domestic” one, chambered for Russian-made 5.45×39 mm cartridges, and an “export” one handling NATO’s standard 5.56×45 mm cartridge. The A-91 assault rifle is compact, user-friendly, reliable, and integrated 40mm grenade launcher.

However, despite all these upsides, the A-91 weighs a hefty 4.4 kilograms, one kilogram more than the workhorse AK-74, and has seen limited acceptance with the Russian Army and some special police forces. It was enough to put this rifle at the Russian Top 5 assault rifles the world doesn’t know.

2. A-94

Developed by the Nikonov Design Bureau in 1994, the AN-94 has been in service with the Russian Armed Forces since 1997. The AN-94 was designed to replace the Ak-74 series.

The stated great advantage of the AN-94 system is its ability to delay the recoil force until fired rounds have left the barrel. This enables more ‘hits’ on a target under the most adverse combat conditions. The AN-94 offers a unique two-shot burst function at a 1,800 rounds per minute rate of fire.

The Nikonov mechanism fires a second shot in burst mode quickly enough to escape before the recoil of the first shot is felt, thus potentially allowing the two shots to hit extremely close together, thus ensuring excellent accuracy.

However, due to its complex design and high production cost, its adoption has been very slow, and its use is currently somewhat limited in service with the Russian Armed Forces. Despite the other produced weapon systems, the AN-94 assault rifle found its place among the Russian Top 5 assault rifles the world doesn’t know the list.

3.  AEK - 971

Developed by the Degtyarev Design Bureau in 1978, the AEK-971 looks much like the AK-74, but at closer inspection, even a non-specialist will find it hard to miss the difference between these two weapons.

Even though the AEK-971 is based on previous AK rifles in internal design and layout, it features a balanced automatic recoil system that reduces the adverse effects of recoil resulting in more controllable automatic fire. For the AEK-971 automatic firing, accuracy is improved by 15-20 percent compared to the AK -74M. 

The A-545 successor to the AEK-971, introduced in December 2014, featured numerous internal and external improvements of the AK-971. The AK-12 has passed state Ratnik trials and will be accepted into service with operational unions for evaluation. 

4. ADS amphibious rifle

The Shipunov Design Bureau developed the ADS assault rifle in 2009 as a dual-medium weapon capable of firing under and above water. It is scheduled to enter service with the Russian Navy’s Special Ops units next year to replace the current APS underwater assault rifle introduced in 1975.  

Russian assault rifle specially made for combat divers. It is of a bullpup layout and is chambered in the 5.45×39mm M74 round. The ADS can be equipped with a suppressor and optical sights. The ADS amphibious rifle also features an integral 40 mm grenade launcher with an effective above—water range of 400 meters.

Its rare ability to serve in water and above water granted its place on the Russian Top 5 assault rifles the world doesn’t know the list.

5. SR -3 "Vikhr" compact rifle

The SR-3 Vikhr is a one-of-a-kind assault rifle, developed by A. D. Borisov, V. N. Levchenko, and A. Tyshlykov   in 1994. Compact and lightweight (2.4 kg), the SR-3 has an effective range of up to 200 meters. 

The SR-3 Vikhr is chambered in a 9×39 mm caliber. It is a powerful SP-6 9×39 mm cartridge capable of cutting through maximum-security body armors from 50 meters away, which is something cartridges used by longer-range assault rifles can’t boast of.

It is a rare weapon often spelled with the 9A-91 assault rifle. It is a compact assault rifle currently in use by Russian police forces. It is a cheaper and versatile alternative to the SR-3 “Vikhr.” The 9A-91 rifle is a gas-operated, rotating bolt weapon, which utilizes a long-stroke gas piston located above the barrel and a rotating bolt with four lugs.