125 mm HEAT-FS ammunition

3BK12M 3VBK10 3BK14M 3VBK16 3BK18M 3VBK17 3BK21B 3VBK25 3BK29M n/avail 3BK37 The HEAT-FS 3BK14M is an improved version of the earlier 3BK12M and replaced it in service. Unlike earlier similar HEAT-FS projectiles of Russian Federation and Associated States (CIS) origin the 3BK14M uses a standoff spike nose to carry the piezoelectric contact sensor for the base fuze. The 3BK18M is a heavier enhancement of the 3BK14M and uses a copper liner for the shaped charge. By contrast the 3BK21M has a Depleted Uranium (DU) liner which improves penetration performance. The 3BK29 reverts to a copper liner for the shaped charge which is optimised for the penetration of active armours. The 3BK37 projectile was first seen during 1993 and is unusual in having three HEAT charges; one in the nose as a preliminary charge, one in the centre to act as a fuze preliminary charge, and the main charge in the base together with a wave shaper charge, each activated in succession from the nose backwards. As far as is known the 3BK37 is still at the development stage. It has been proposed that the techniques employed with this projectile could be carried over to 100 and 120 mm projectiles. As a typical example, the T-72 usually carries a combat load of 39 rounds, of which only six are HEAT-FS. This reflects the accepted ballistic limitations of the HEAT-FS projectile to the extent that it has been almost entirely replaced by APFSDS-T projectiles for most anti-armour fire missions. A new munitions plant is to be built at Bolangir in Eastern India which, when fully operational, will be able to produce 150,000 rounds of 125 mm ammunition every year. This will presumably include HEAT-FS projectiles. Description In common with the rest of the 125 mm ammunition range, HEAT-FS is a separate loading munition. The projectile is automatically loaded into the breech followed by a semi-combustible propellant case. Projectile bodies are steel and encircled by a single sintered iron driving band 6.86 mm wide. The front of the projectile carries a standoff spike inside which is a piezoelectric contact sensor connected by an internal wire to a base-mounted fuze. The fuze used on the 3BK14M is the V-15 or VG-15 while later models use the 3B15 (3BK18M) or VU-729 (3BK21P). When the fuze functions it ignites the main explosive filling which varies from model to model, resulting in hard target penetration plus fragmentation effects. The explosive filling (usually A-IX-1 or OCFOL) forms a conical shaped charge set behind a liner. The rear of the projectile body carries an extension on which are carried six forward-folding steel fins. The hinged fins snap out once the projectile has left the gun muzzle. The triple-charge warhead 3BK37 weighs 19 kg and has a direct fire range of 1,010 m; maximum aimed range is 4,000 m. Penetration against 60º armour is given as 350 mm following the destruction of reactive armour. Projectiles are fired using a semi-combustible charge case known as the Zh52 and weighing 10 kg; the charge case for the 3BK14M weighed only 5.885 kg. The cases are nitrocellulose impregnated with TNT. A GUV-7 electrical primer is fitted. After firing, a steel stub case weighing 3.4 kg remains to be automatically ejected, although manual ejection may be employed. The case, made of BW 11 steel, is 140 mm long with the flange diameter being 171.9 mm. Most HEAT-FS projectiles have a muzzle velocity of 905 m/s. The 3BK14M warhead can defeat up to 220 mm of armour at 1,000 m, although at that range the probability of a first time hit on a static target has been calculated as 73 per cent. At 1,500 m the hit probability falls to 36 per cent. The maximum direct fire range is around 4,000 m, although at that range accuracy is negligible. The penetration performance of the 3BK18M is not known for certain (a penetration of 260 mm of armour has been estimated) and neither is that for the 3BK21B or the 3BK29. It is known that the 3BK29 is fired with an increased muzzle velocity of 915 m/s and it has been estimated that the 3BK29 warhead could penetrate 300 mm of armour following the detonation of active armour. It has been claimed that the triple-charge warhead 3BK37 can penetrate 350 mm of Rolled Homogeneous Armour (RHA) at an angle of 60º. It is claimed that all these types of round have a service life of up to three years in a tank gun autoloader. Normal shelf life under controlled conditions is of the order of 10 years. The training round used for the latest types of HEAT-FS projectiles is the HEAT-FS-TP 3VP11 using the 3P11 projectile; ealier models used the 3VP5 with the 3P11 projectile. The HEAT-FS-TP 3P11 projectile does not contain explosive but is an exact ballistic match for operational projectiles such as the 3BK18M out to a range of 4,000 m. Weight of the training round is 29 kg complete, 19 kg of which is the projectile. The normal Zh52 propelling charge is employed and handling and loading procedures are identical to those for operational rounds. Authorised fuzes PIBD V-15, 3V15 or VU-729 Equivalent rounds BULGARIA BULGARIA Manufacturer Kintex Type: 125 mm VBK10 round with BK14M hollow charge projectile Description: Essentially as described in text but projectile weight given as 19 kg and length 628 mm. Manufacturer Duna-Rit Type: 125 mm HEAT Description: Exact model uncertain but probably 3BK18M. Weight of projectile 19 kg, muzzle velocity 905 m/s and fitted with PIBD V-15 fuze. Armour penetration given as 200 mm with armour set at 60º. IRAN Manufacturer Defence Industrial Organisation, Ammunition Group Type : 125 mm HEAT-T Description: Exact model uncertain and weights as other data differ considerably from those from other countries of origin. Specifications provided state that total round weight is 33 kg with the projectile weighing 23 kg. The shaped charge weight is given as 3.4 kg of RDX. Muzzle velocity is 850 m/s. This round may be a local development. POLAND Manufacturer Zaklady Produkcji Specjalnej Sp Zoo (ZPS) Type: HEAT-T Description: Believed to be equivalent to the 3BK18M. Weight of projectile is 9.5 kg, fitted with PIBD W-15 (V-15) fuze, and contains 1.52 kg of explosive. Muzzle velocity is 905 m/s. Accuracy spread at 1,000 m is 0.3 × 0.3 m and 0.6 × 0.6 m. The round can penetrate 400 mm of RHA plate at between 80 and 100 m Manufacturer Presta Type: 125 mm HEAT-T Description: Exact model uncertain but believed to be equivalent to 3BK18M. ROMANIA Manufacturer SN ROMARM SA Type: 125 mm HEAT-FS-T BK-14M Description: Standard specifications. RUSSIA Manufacturer Rosoboronexport Type: HEAT-FS 3VBK16 round with 3BK18M projectile; 3VBK25 round with 3BK29M projectile Description: Standard specifications, see text UKRAINE Manufacturer TACKO Type: HEAT-T 3VBK10 and 3VBK16 Description: Standard specifications. HEAT Practice also available. YUGOSLAVIA , FEDERAL REPUBLIC Manufacturer Yugoimport - SDPR Type: M88 with HEAT-T Description: Explosive filling is 1.75 kg of F04P (HMX). Fuze is UT-PE, M87 and primer KT-UE, M84 . Muzzle velocity given as 905 m/s. Intended for use on M-84 and M-84A tanks, the Yugoslav versions of the T-72 . May no longer be in production