About the RPG-7 grenade, which penetrates almost a meter of steel armor
The ammunition range of the legendary Soviet RPG-7 grenade launcher includes a lot of anti-tank ammunition, which includes the PG-7VR round with the PG-7R tandem cumulative grenade, which is still actively used today. Successfully overcoming dynamic protection, it is capable of penetrating at least 600 mm of solid steel.
It’s another matter when the target does not have this very dynamic protection. In this case, the armor penetration of the grenade increases to impressive values.
The last of the anti-tank
Generally speaking, the range of anti-tank (armor-piercing) ammunition for the RPG-7 is really quite large. The fact is that after the grenade launcher was put into service in 1961, Soviet engineers tried in every possible way to maintain the relevance of this product on the battlefield, developing and introducing into mass production grenades with increasingly higher penetrating ability, in order to forestall the strengthening of the armor of Western tanks.
So, if in the same 1961 the PG-7 grenade (PG-7V shot) of 85 mm caliber, adopted for service together with a grenade launcher, pierced about 260 millimeters of steel armor at a right angle, then almost eight years later it was presented as a replacement a modernized version of the PG-7M (PG-7VM) with a caliber reduced to 70 mm and armor penetration increased to 300 mm.
Already in 1972, the third grenade PG-7S (PG-7ВС) of 72 mm caliber was adopted, the penetration of which was increased to 400 millimeters by improving the shape of the cumulative funnel, reducing the speed of rotation of the grenade in flight and introducing a more powerful charge from okfol. A simplified version of the shot was also produced under the name PG-7VS1, whose grenade was equipped with a cheaper explosive and could penetrate about 360 mm.
Rounds for RPG-7 from left to right: PG-7VM, PG-7VS, PG-7VL, PG-7VR, as well as thermobaric TBG-7V and fragmentation OG-7V
In the same 70s, the transition of Western tank building to combined armor, potentially reducing to zero the characteristics of the RPG-7 shots available to the Soviet Army, began to be clearly outlined. Therefore, in 1977, the PG-7L “Luch” (PG-7VL) grenade with an armor penetration of 500 millimeters was adopted. This was achieved by increasing the caliber of the grenade to 93 mm and increasing the mass of the explosive, which led to a significant reduction in its initial speed and target range.
The fifth (formally sixth, if you count the PG-7VS1) and last on this list was the heroine of this material - the PG-7R “Resume” grenade, adopted as part of the PG-7VR round in 1988. The impetus for its development was the combat use of dynamic protection on Israeli tanks and the possible spread of “reactive armor” on armored vehicles of other countries.
Today, this grenade is considered the most powerful in the RPG-7 ammunition package - and a replacement for it, as they say, has not yet been “delivered”, since after the collapse of the USSR, the domestic industry did not provide more powerful anti-tank ammunition in a serial version.
Heavy, slow, powerful
As is known, dynamic protection has an extremely detrimental effect on the armor penetration of cumulative ammunition - on artillery the shells are slightly smaller (due to their mass, speed and thick walls), and anti-tank grenades and missiles stronger. The mechanism of this influence is the impact of the explosion energy of the dynamic protection unit and the plates moving at high speed, which disrupt the integrity of the cumulative jet.
To mitigate or completely eliminate these effects, tandem cumulative weapons are used - the same shells, grenades and missiles, equipped with two (sometimes three) cumulative charges. One of them is the leading one and is intended to prematurely initiate detonation in the dynamic protection unit, and the second, being the main one, penetrates the armor directly with a slight delay.
The PG-7R grenade belongs to this class.
Its design uses two coaxially located shaped charges. The first - the leading one - has a caliber of 64 millimeters, taking into account the thickness of the case, and is equipped with 120 grams of okfol with a cumulative lining (funnel) made of aluminum alloy. The second - the main one - is already much thicker: 105 millimeters in caliber with a copper funnel of variable thickness and a charge weight of the same okfol of 1,2 kilograms.
PG-7VR shot device: 1 – fuse head, 2 – leading charge, 3 – main charge, 4 – propulsion system
The product, it must be said, thanks to this design, turned out to be quite dimensional: if the length of all previous shots for the RPG-7 ranged from 925 to 990 millimeters, then for the PG-7VR it reached 1 mm. In this regard, it was even necessary to introduce a threaded connection between the warhead and the engine with the propellant charge, so that it would be possible to divide the shot into two parts for carrying and storage.
The mass of the shot also became significant - 4,5 kg. For example, in the predecessor of the PG-7VR, represented by the PG-7VL, as the heaviest of the cumulative grenades, it was 2,6 kilograms. Considering that the “Resume” propulsion system was taken from the same “Luch” with modifications in terms of stabilizers, the kilograms affected the direct shot range (140 meters for the PG-7VR versus 240 for the PG-7VL) and the target firing range, the indicator of which was at level of 200 meters with a standard sight at that time, which is lower than all RPG-7 grenades of previous releases.
In addition, due to the large mass of the grenade, it has a record low maximum flight speed among all RPG-7 anti-tank ammunition - only 120 meters per second. However, you can learn more about the differences in the performance characteristics of the shots in the table below.
Yes, the grenade turned out to be heavy, slow, and not always convenient to handle and especially to shoot due to the strong “preponderance” forward when aiming at the target. But at the same time powerful: successfully overcoming mounted dynamic protection with the help of a leading charge, including the Soviet “Contact”, it is capable of penetrating at least 600 millimeters of solid steel at a right angle - an armor thickness unthinkable by the standards of Soviet grenade launchers of those times.
By the way, the same grenade design was used in the creation of the PG-29V shot for the equally famous RPG-29 “Vampire” grenade launcher, as well as the RPG-27 “Meadowsweet” ammunition. Therefore, their armor penetration characteristics are generally identical.
When there is no dynamic protection
Well, with dynamic protection and penetration behind it, everything is clear, but how much does this indicator change if the target does not have “reactive armor” and both grenade charges - the leading and the main - work off the “passive” armor? Here, as in the case of other tandem cumulative ammunition, whose charges are located coaxially, the principle of a sort of partial addition works.
In other words, the cumulative jet of the main charge penetrates into the shallow hole (cavity) already formed by the leading charge in the armor, due to which its penetration increases. Of course, this effect depends on many circumstances: the accuracy of ammunition manufacturing, armor inclination angles, the penetration ability of the leading charge, flight speed, the difference in the thickness of the cumulative jets of the leading and main charges, the firing distance of the main charge from the armor, and so on.
However, in general, the increase can reach several tens of percent. In general, it is with these “estimates” that the armor penetration of the PG-7R is often indicated in various reference books and other materials - somewhere they write that 700-750 millimeters, and, for example, the textbook “Weapons and Ammunition” from MSTU. . Bauman gives the upper limit of grenade penetration at 800 millimeters.
As for the real maximum results of the grenade, here it is worth turning to full-scale tests conducted many years ago by Ukrainian researchers from the Microtek BCCT.
During these executions, a grenade was detonated on a built-up barrier 800 millimeters thick, consisting of an assembly of steel sheets. By the way, there is no conspiracy theory in a set-up barrier: it’s easier to regulate the thickness of the armor being fired at, you don’t need to carry a heavy metal block of enormous thickness, and the hardening (and other properties) of the barrier are thus uniform, which cannot be ensured in a solid sheet a meter thick.
Well, in fact, the result itself: the successively detonated PG-7R charges pierced through this set of steel plates. Moreover, the cumulative jet, having overcome a distance of 1,6 meters in the air after breaking through the barrier, pierced a separate slab 92 millimeters thick. In this case, we can actually say that the maximum armor penetration of a grenade without dynamic protection can reach 900 or even more millimeters of armor at right angles.
Много это или мало?
Sometimes you can often come across opinions that anti-tank grenade launchers, being portable and actually “pocket” means of close combat with armored vehicles, are a priori weaker than any anti-tank guided missiles. But this, of course, is not true.
The PG-7R, if the target does not have dynamic protection, penetrates more than most monoblock missiles. This applies to the ammunition of the famous Metis ATGM, which penetrates less than 600 millimeters. And the Konkurs and Fagot missile systems. The American TOW and Dragon can also be included in this cohort - their “monoblocks” cannot keep up with the PG-7R either. But all this, let’s say, is just comparisons.
More noteworthy is the fact that with the RPG-7, equipped with this tandem grenade, at the time of its creation and adoption it was possible not only to hit the sides, but also the foreheads of modern Western tanks at that time - they still did not have dynamic protection .
PG-7VR shot in carrying position
For example, the forehead of the turret of the German Leopard 2A4, as the most protected place, produced up to 700 millimeters in steel equivalent from the “cumulative”, according to British data. Moreover, the installation of new armor packages, carried out on this series of tanks since 1988, also did not provide a complete guarantee of protection, since its indicators varied within 750-800 mm from cumulative weapons.
A similar situation was with the English Challenger, whose turret front gave out the equivalent against cumulative shells in the region of 700 millimeters. And you shouldn’t forget about the American “Abrams” model M1A2: if the front of its turret could still provide 900 mm equivalent, then the body at the heading angles - no more than 750 millimeters.
The pomegranate has not lost its relevance today, albeit with some conventions. Of course, you can’t go head-on with modern Western tanks with it - the same “Leopards 2A6/2A7” or “Abrams” SEP v.3 most likely won’t even notice hits, so only on the side and vulnerable spots. But for the same special operation in the event of close combat, the PG-7R is what is needed. With equal success, it can, with a high probability, purchase almost any Soviet-designed tank, even with dynamic protection (the exceptions are the T-72B and T-80U), and “stubs” in the form of the M1A1SA Abrams and the aforementioned Leopard 2A4, too.
Information sources:
“Domestic anti-tank grenade launcher systems”, A. Lovi
“Weapons and ammunition”, A.V. Babkin, V.A. Veldanov, E.F. Gryaznov and others.
Information