The BMP-23 infantry combat vehicle was developed by the Bulgarian defence industry to meet the operational requirements of the Bulgarian Army.

It is based on a redesigned Russian-developed MT-LB multipurpose tracked vehicle chassis that has also been manufactured in Bulgaria, which in turn shares a number of common components with the Russian 122 mm 2S1 self-propelled artillery system. Both of these have been manufactured under licence in Bulgaria for the home and export markets by the BETA Joint Stock Company.

The BMP-23 and BMP-30 infantry combat vehicles have been manufactured by the TEREM Joint Stock Company. It is understood that there has been no recent production of the BMP-23 infantry combat vehicle. It is understood that marketing of both vehicles has now ceased.

The hull and turret of the BMP-23 infantry combat vehicle are of all-welded steel armour construction providing the crew with protection from small arms fire and shell splinters. The highest level of protection is provided over the frontal arc of the BMP-23.

The engine compartment is to the immediate rear of the front crew members with access hatches provided in the roof. The exhaust outlet is on the right side of the hull with the air inlet and outlet louvres being in the roof on the left side, in a similar arrangement to the Russian MT-LB.

No details of the diesel engine installed in the BMP-23 are available apart from its output of 315 hp. However, both the MT-LB and the 122 mm 2S1 are powered by a YaMZ-238V V-8 water-cooled diesel developing 240 hp at 2,100 rpm. The diesel engine is coupled to a manual transmission with five forward gears and one reverse.

Behind the transmission, seated on the left side of the vehicle, is the driver, who steers using conventional tillers.

Access for the driver is provided by a single-piece hatch cover that opens to the rear and in front of this hatch are three forward-facing day periscopes that provide observation over the frontal arc when driving closed down. The central periscope can be replaced by a passive night observation device.

Suspension is of the torsion bar type with seven rubber-tyred road wheels each side, drive sprocket at the front with the idler at the rear. There are no track-return rollers.

The two-man power-operated turret is on the centre-line of the vehicle roof with the gunner on the left and the commander on the right. Turret traverse is a full 360° with maximum weapon elevation +80°.

The main armament consists of a 23 mm 2A14 cannon fitted with a muzzle brake flash suppressor and is also used in the ZU-23-2 twin 23 mm towed anti-aircraft gun system which is known to have been produced in Bulgaria for the home and export markets. A 7.62 mm PKT machine gun is mounted coaxially to the right. The 23 mm cannon fires HE-IT and AP-IT ammunition with a muzzle velocity of 970 m/s. Maximum vertical range is 1,500 m and maximum horizontal range is 2,000 m. The 7.62 mm PKT machine gun fires 7.62 × 54R mm cartridges with a maximum muzzle velocity of 827 m/s and a maximum effective range of 1,500 m.

The 23 mm 2A14 cannon day sight has a magnification of ×4.5 and a 40° field of view, while the 7.62 mm machine day gunsight has a magnification of ×5.5 and an 11° field of view.

On the roof of the turret is a launcher for the Russian Kolomna KBM 9K11 Malyutka (AT-3 'Sagger') ATGW with a maximum range of 3,000 m. The missile is launched by the gunner from within the safety of the vehicle and an additional three locally manufactured Russian Kolomna KBM 9K11 Malyutka (AT-3 'Sagger') missiles are stowed vertically to the rear of the turret for manual reloading.

The 9K11 Malyutka (AT-3 'Sagger') was designed by the Russian KBP Instrument Design bureau but has been manufactured under licence in Bulgaria by the Vazov Engineering Plant in Sopot.

At the rear of the turret, opening to the left, is a small rectangular door that is believed to be for ammunition resupply purposes.

The gunner has a single-piece hatch cover that opens to the left and there are day and passive night sights mounted on the forward part of the turret roof. The night sight is believed to be of the image intensification type.

The commander of the BMP-23 is provided with a forward-opening hatch cover with three day-only periscopes and a night searchlight, which can be operated from within the turret.

The infantry compartment is at the rear of the hull with the six infantrymen seated in two rows of three, back-to-back. The troops enter the vehicle via two doors, opening outwards, in the rear of the hull.

Over the top of the troop compartment are two roof hatches. The main diesel fuel tank, like that on the BMP-1/BMP-2, is located in the centre of the rear troop compartment, with the seats either side. A locally produced, Russian-designed Strela-2 (NATO SA-7 'Grail') man-portable SAM is carried above the fuel tank.

One of the seven infantrymen is seated at the front of the vehicle on the right side with a hatch, three roof-mounted day periscopes and a firing port. To his right is a firing port for a 7.62 mm AK-47 assault rifle and rockets for the RPG-7 launcher. There are eight firing ports provided in the rear troop compartment, three on each side and one on each of the rear doors, all ports have associated firing blocks. The first firing port either side is for a 7.62 mm PK machine gun while the other six are for 7.62 mm AK-47 assault rifles.

In addition to the 23 mm 2A14 cannon, 7.62 mm PKT coaxial machine gun and Russian-designed 9K11 Malyutka (NATO AT-3 'Sagger') ATGW launcher, the following weapons are carried for use by the infantrymen:

1 × SA-7 man-portable SAM

1 × RPG-7 rocket launcher and five upguided rockets

4 × RPG-22 light anti-tank weapons

2 × 7.62 mm PK machine guns, each with 600 rounds

6 × 7.62 mm AK-47 assault rifles each with 240 rounds

20 × hand grenades

18 × signal flares

The BMP-23 is fully amphibious and is propelled in the water by its tracks. Before entering the water the bilge pumps are switched on and the trim vane erected at the front of the vehicle. To enable the driver to see above the erected trim vane, the standard day periscope is replaced by an extendable one. When the trim vane is not required, it is folded back onto the glacis plate.

Like the 2S1 122 mm self-propelled howitzer, a slotted device to improve water flow is attached to either side of the hull at the very front alongside the drive sprocket; when not required the device is stowed on the hull side.

Standard equipment includes a fire detection and suppression system, a heater, a fume extractor for use when the weapons are being fired from within the vehicle, a GPK-59 course corrector, a UHF communications system with a range up to 20 km, internal vehicle lighting and a system that allows the BMP-23 to lay its own smoke screen by injecting diesel fuel into the exhaust.

This is similar to the BMP-23 but has a bank of three 81 mm smoke grenade dischargers on either side of the turret firing forwards and new road wheels. The roof-mounted 9K11 Malyutka (AT-3 'Sagger') has been replaced by a launcher for the Tula KBP 9K111 Fagot (AT-4a/b 'Spigot'). This is only used by Bulgaria.

There is a separate entry for this vehicle, which is only used by Bulgaria.

This is essentially the chassis of the BMP-23 fitted with the complete two-man turret of the Russian BMP-2 ICV. Details of this are given in a separate entry. Production is complete and it is no longer marketed.