In my erstwhile text, I presented to you the state of cognition of the 3UBR11 subcalibre anti-tank ammunition, which was presented by the Russians as the future a fewer years ago. However, the fact is that due to the unresolved construction problems of Russian combat wagons a fewer decades ago, This is about 3UBR11 as well as more celebrated 3UBR8. However, there is another kind of ammunition that could be placed in the hands of Russian soldiers, which would truly rise the capabilities of Russian BMP and BTR in the fight against Ukrainian and NATO-wish combat vehicles. We are talking about a full caliber anti-tank rocket (APCR type) 3UBR7 Trizubek.
Aircraft kind 9-A-4543 anti-tank ammunition
The deficiency of cognition of this projectile in the West is due to the fact that we are dealing with an APCR missile, which in the light of the presence of subcalibre anti-tank missiles (APDS and APFSDS) is considered obsolete. At the same time, 3UBR7 could only be produced in the form of tiny prototype parties, formally adopted for the arms of the Russian armed forces and inactive not ordered. However, the existence of specified ammunition in Russia is due to any nonsubjective reasons.
Such a rocket plays a greater function in Russian military aviation, where it was implemented under designation 9-A-4543. The aim of the implementation of this ammunition was the problem of utilizing ammunition with the discarded sabot, which for airmen was a troublesome issue. At the same time, the military wanted ammunition of this kind with a hard core to have akin ballistics to full caliber anti-tank ammunition with a steel core. This was due to the fact that the aim of this request was to usage harmonised firing tables for steel core and hard core ammunition, which would reduce the training time of soldiers from the usage of different anti-tank ammunition and destruct the problem of making adjustments in the targeting grid of the previously utilized targeting instruments. For this reason, both APCRs were designed to get identical aerodynamics and mass comparative to the 3UBR6 rounds (for 3UBR7) and 9-A-4511 rounds (for 9-A-4543). Due to the advanced density of the proposed core materials ( tungsten carbide, tungsten alloy and uranium alloy), designers were doomed to compromises that were contrary to the existing assumptions for the plan of ammunition with a hard core. As a result, the full possible of specified anti-tank ammunition has not been drawn from these structures.
Comparison of appearance of kind 3UBR6 anti-tank ammunition (top and mediate projectile) and 3UBR7 (lower projectile)
Type 3UBR7 ammunition characteristics
The main problem was to accomplish an adequate mass of the full projectile, which must be about 400 grams, which besides included the mass of the core used. The bullet could not be besides dense due to the usage of the same propelling material as in 3UBR6 ammunition. In addition, another mass of the projectile would besides affect its aerodynamics. For this reason, the compromise reached had to concern the form and size of the core of advanced density material.
In line with the assumptions developed during planet War II for the plan of armoured ammunition with a hard core, it was established that:
- the ratio of the hard core diameter to the bullet diameter shall be 1 : 1,8 – 2,8,
- the ratio of the dimension of the hard core to its diameter shall be 3,5 – 4 : 1,
- the ratio of the dimension of the hard core to the diameter of the projectile shall be 1,3 – 2 : 1,
- the aim should be to accomplish the maximum exit velocity of the projectile.
These assumptions were utilized to plan all russian APCR/HVAP kind anti-tank missiles, as well as during the Cold War period, they were utilized to plan steel sub-caliber carbide cored anti-tank missiles (including 3BM15 to T-72 and 3BM20 to T-55AM Merida). According to them, the penetrator designed for the APCR 30 mm caliber projectile should have a diameter of 11 – 16 millimetres and a dimension of 39 – 60 millimetres. Moreover, specified dimensions would let the usage of specified a penetrator either in 23 and 35 mm caliber ammunition or 35 and 45 mm caliber. Of course, this will most likely never happen, due to the fact that APCR ammunition is an obsolete kind of armor-piercing ammunition.
In fact, the assumptions made before the APCR ammunition penetrator
30 millimeter, they were completely different. According to them:
- the ratio of the hard core diameter to bullet diameter shall be 1 : 1,15 – 1,2,
- the ratio of the dimension of the hard core to its diameter shall be 1.36 : 1.46 – 1,
- the anterior part of the core can be narrowed at an angle of 13-17°,
- the tip shall have an beginning angle of 118 to 120°.
Tank rocket section 3BR7
As a result, the hard core utilized in 3UBR7 kind ammunition is 25 – 26 millimetres in diameter and 34 – 38 millimetres in length, with a weight of about 245 grams. The constructors explained specified selection of core dimensions the anticipation of expanding armor penetration by this kind of projectile. However, it cannot be hidden that the mention point was not another proposals for HVAP/APCR kind missiles, but a 3BR6 kind steel projectile.
Speaking about the effectiveness of 3BR7, the designers adopted the mention test cover for its assessment, which was tilted at an angle of 60°, a steel panzer plate with a thickness of 20 millimetres. The standard 3BR6 beats this armor from a distance of 800 m, while 3BR7, depending on the material utilized for the hard core, pierced this shield from a distance of 1500 to 2,000 m. Paradoxically, the best consequence was achieved utilizing a tungsten carbide core, containing an additional 15% cobalt (designation: WK15), where this armor was pierced at an impact velocity of only 550 m/s, corresponding to a distance of about 1950 m. For comparison, a circular with a tungsten core pierced this shield from a distance of about 1,500 metres, and a circular with a uranium core – from a distance of about 1450 metres. The constructors themselves indicate the distances from which the test shields were pierced as larger by about 200 metres, which may indicate that 3BR7 was inactive slower than 3BR6. The impact on this consequence may have been higher hardness of this material against tungsten and uranium alloys while at the same time unnecessary increased core plasticity. Therefore, 3UBR7 may possibly be cheaper in production than the more modern 3UBR8 and 3UBR11.
Although 1 mention mentions that despite the results received
It was decided to usage depleted uranium as a core in a 3BR7 missile. This may be affected by an effective full caliber scope of 30 mm x 165 ammunition, which does not exceed 1500 metres. However, the lower outlet velocity makes this ammunition completely ineffective against composite shields containing ceramic layers. At this point, however, this would not disturb the Russians due to what armored infantry vehicles are presently facing in Ukraine.
The second information we know about the penetration of 3BUR7, although derived from aviation data 9-A-4543, is the ability to pierce a 60° angled steel armor plate with a thickness of 25 millimetres at a distance of 1000 metres. This besides clearly indicates that this ammunition is adequate to withstand shields designed to defend against kind 3UBR6 ammunition. However, this is worse than the NATO-developed 23 mm APDS subcalibre ammunition.
Lessons for Us
From our point of view, 3UBR7 ammunition can only be a curiosity, but it is worth considering. The main advantages of this ammunition are the increased penetration of steel armour against the standard in the Russian forces of kind 3UBR6 anti-tank ammunition and the anticipation of Russian combat vehicles utilizing this ammunition without the request to modify the 2A42 and 2A72 high-speed cannons. It is so desirable that Borsuk's armour should warrant protection against this kind of ammunition.
However, the usage of the uranium core may be the reason why we will not see ammunition in its first form during fighting in Ukraine. The cognition available may besides propose that this ammunition could be right if carbon cores were to be produced for it. Only here is the problem of utilizing as much as 15% mass cobalt in the material erstwhile the first accessories for the possible usage of WK3 cermet (i.e. tungsten carbide from 3% cobalt) in tiny caliber anti-tank ammunition appear.
I myself am incapable to make a clear assessment of whether it will be profitable for the Russians to implement specified ammunition for front units. For this moment, I leave this motion for you.
Bibliography
- patent RU 2119639 C1, Бронебойный подкалиберный для малокалиберного малокалиберного, W.I. Doom, M.J. Leontiew, A.W. Smirnow, announced and awarded 27.09.1998
- patent RU 2247304 C1, Артиллерийский малокалиберный патрон, B.M. Butajev, R.U. Esiev, W.I. Doom, A.I. Kosichin, A.W. Smirnow, O.T. Cziżewski, announced and awarded 27.02.2005
- Santa Kulesz, Some aspects of the plan and plan of subcalibre anti-tank missiles, Bulletin of the Military method Academy, vol. 4 (1955), No. 9 (53), pp. 3 - 11
