Why don't the marshals and generals have a good impression of the armor-piercing bullet? In fact, this has to start with a certain immortal. Before the outbreak of World War II, Li Xiaofeng vigorously advocated the development of armor-piercing ammunition, which made the use of the Monroe effect of anti-armor ammunition develop rapidly.

If it weren't for Li Xiaofeng's efforts to stand up for tanks and armored troops, and if it weren't for Tukhachevsky's use of power to promote the theory of large-depth operations, I am afraid that the Soviet Union's tank development would have suffered a heavy blow in this time and space.

Let's put it this way, at that time, Soviet military strategists and military technologists sang praises to armor-piercing shells, and the supporters of armor-piercing shells who supported the development of high-pressure long-barreled artillery were a little unwilling.

However, in the Spanish Civil War, a large number of Red Army tanks and anti-tank guns equipped with armor-piercing shells did not perform well, such as 37 mm and 45 mm armor-piercing shells, which could theoretically penetrate 70 mm to 90 mm armor plates in terms of armor-piercing theory at the time, and could also penetrate armor plates ranging from 60 mm to 80 mm in live fire tests at the shooting range. But in actual combat, its armor-piercing power is simply pitiful, and it can only penetrate homogeneous armor plates 10 to 20 mm thick.

Why is there a huge difference between theory and practice, and between the shooting range and the actual data? The reason is simple, these theoretical figures are all figures derived from an ideal state under ideal conditions. For example, how to test the power of armor-piercing bullets at the shooting range?

In fact, it is not a live shot, but an armor-piercing projectile is placed in front of the target plate in a fixed and ideal state to detonate, which is also known as the static armor-piercing value. And in real combat, the armor-piercing shells fired by rifled guns are rotating at high speed (tens of thousands to 100,000 revolutions). The centrifugal force disperses the jet greatly. The natural kinetic armor breaking value is miserable.

This was also before the outbreak of World War II. An important reason why Li Xiaofeng especially wanted to develop the 100 medium-chambered smoothbore gun. From the beginning, this cannon was prepared for armor-piercing shells, which can maintain the power of armor-piercing shells to the maximum.

Of course, this gun has indeed done this, for example, theoretically, the maximum static armor-piercing capacity of a 100 mm caliber armor-piercing projectile is about 500 to 700 mm (depending on the material and taper of the medicine cover), if it is fired with a rifled gun, the dynamic armor-piercing ability is about 100 mm, and when fired with a smoothbore gun, how much is the dynamic armor-piercing ability? It's probably between 200 mm and 300 mm. That's almost a threefold difference!

Let's put it this way. In the case of the 100-mm smoothbore gun currently equipped with the T-54, it can easily penetrate even if it encounters the German E-100. Even on the battlefields of the Great Patriotic War, it often appeared that the T-54 would beat the opponent through the opponent.

Seems like that's good! Yes, the armored corps of the Red Army was quite satisfied with the power of the 100-mm medium-chambered smoothbore gun to fire armor-piercing shells, but was extremely dissatisfied with the accuracy of this gun! Because of the relatively low chamber pressure, the effective range of the gun is very limited, basically it can only attack targets within 750 meters, beyond this distance, the accuracy is miserable. It's not just the armor-piercing bullets that are fired with ugly accuracy. Firing grenades is just as ugly, as a heavy tank dedicated to supporting infantry breakthroughs. Working with grenades is a must-have skill. The problem is that this essential skill, the 100mm medium-chambered smoothbore gun, is really not practiced well.

So the armored forces actually have quite an opinion on this, and in the improvement of the T-54, the key item is this gun. Before the outbreak of the Great Patriotic War, the Panzer Corps instructed Petrov, the chief designer of the Ural Heavy Machinery Plant, to develop a 100-mm high-pressure rifled gun (that is, the D-34 series) based on the B10 naval gun.

Had it not been for the sudden outbreak of war, and the technical difficulties faced by the armor-piercing shells used in the D-10 series (the scrap rate was too high), the Panzers would have been ready to replace all the 100mm medium-chambered smoothbore guns on the D-54 with the D-10T.

So at this time, as soon as they heard that the D-5T was using armor-piercing shells, the marshals and generals immediately cooled down by half, because they were really fed up with armor-piercing bullets that looked good.

"This is a brand-new armor-piercing projectile," Li Xiaofeng was not in a hurry at all, and explained slowly: "In order to solve the problem of insufficient armor-piercing and armor-piercing capabilities of the existing armor-piercing projectile, NORINCO has carried out a series of technical improvements. The NVK-150 series armor-piercing projectiles you see now are the latest technological achievements. Its accuracy at up to 1000 meters is no significantly different from that of armor-piercing shells, and it is capable of penetrating vertical armor up to 150 mm thick...... And everyone should have seen the effect of this new armor-piercing projectile just now, which is far superior to the BR-271N armor-piercing projectile, which is expensive, difficult to produce, and requires tungsten carbide. ”

This explanation reassured the generals a lot, but Tukhachevsky was willing to admit defeat so easily, he attacked: "It's just what you said!" ”

Li Xiaofeng pointed to the target board speechlessly, the meaning was very clear, the three rounds of shooting just now had explained everything. However, Tukhachevsky still refuses to admit defeat: "It still doesn't mean much, who can guarantee that this is not the best ammunition that you have specially selected, and it has not been tested with a lot of live ammunition at the national range......"

Before he finished speaking, Li Xiaofeng interrupted: "So the BR-271N has been tested by the National Range again?" I'm sorry, but it's still a product in the lab, and it's not even qualified to go to the production line. And the NVK-150 can already be mass-produced and equipped with troops, and as for the tests of the national range, they can start at any time! ”

The generals nodded with satisfaction, for them, the most advanced and best but untouchable ammunition is meaningless, they need shelf products, they need products that can be equipped in large quantities very quickly. And in this regard, the NVK-150 undoubtedly has a huge advantage, and this advantage also gives the D-5 series a considerable advantage. If the D-5 series has no problems fighting tanks, and the multi-purpose capabilities are far superior to the ZIS-2, then it is not clear who to choose?

So how did Li Xiaofeng do this? Or what method did he use to solve the problem of insufficient armor-piercing ability of rifled guns to fire armor-piercing bullets?

In fact, there is no way to solve this problem at all. Yes, no kidding at all, this is a problem that there is absolutely no way to solve fundamentally. Because rifled guns because of the reason they were born. It is not suitable for firing armor-piercing shells.

The high-speed rotation inevitably disperses the jet. It will inevitably affect the ability to pierce armor. Unless the shells stop spinning, the problem can be solved once and for all. The question is, is this possible for rifled guns?

It was completely impossible, and countless experts for decades had been trying to figure out how to help the rifled gun, and in the end, it was only to optimize the rifled gun's ability to fire armor-piercing shells. The most famous one is the French G-type armor-piercing projectile, and the other is the sliding belt technology invented by Niu Niu. The former claims to be able to reduce the rotation of the armor-piercing bullet from tens of thousands of revolutions to 20 revolutions, while the latter also claims to be able to reduce the rotation speed of the armor-piercing bullet by half.

Is it that good? I only know when I use it. In the sixties, the Jews introduced the Gallic Chicken's CN-105-57 105mm rifled gun and the exclusive G-type armor-piercing shell. Please note that this is a "magic weapon" specially made by the Gallic chicken to fire armor-piercing shells, because of the low chamber pressure, in fact, it is basically unable to fire kinetic armor-piercing shells, and it is claimed to be able to penetrate armor by 360 mm (vertical) at a maximum effective range of 700 meters.

And what about the actual combat results? In actual combat, the Jews found that the theoretical minimum speed of 20 revolutions of the G-type armor-piercing projectile was basically impossible to achieve, and the rotation speed of the armor-piercing projectile was still as high as several thousand revolutions, and the result was that the theoretical armor-piercing value of 360 could not be achieved at all. Not to mention dealing with the thicker armored T-62, even the T-54 is quite difficult. As a result, the Jews quickly phased out the flashy and costly G-type armor-piercing shells. Throw it in the garbage along with the CN-105-57.

As for the sliding elastic belt invented by Niu Niu, it has to be said. This is indeed simpler than the French idea, easy to implement and inexpensive. But this still does not solve the root cause. The armor-piercing projectile using the sliding belt technology still has a speed of up to 10,000 revolutions after launch, and its dynamic armor-piercing power is actually only one-third or even one-quarter of the power of the static armor-piercing projectile. It's still just looking good.

So how did Li Xiaofeng increase the power of the NVK-150 armor-piercing projectile? He divided into several steps, the first of which was to improve the old mechanical fuse into a piezoelectric fuse.

Why make such improvements? Although the armor-piercing projectile has a high theoretical breaking value, it requires the metal jet of the armor-piercing projectile to reach an optimal distance to detonate (that is, the optimal explosion height), and only at this distance can the metal jet with the smallest cross-sectional area and the highest density be obtained. If the detonation is too late, the metal jet will hit the armor plate before it reaches the most dense level, and the natural power will be greatly reduced; If the detonation is too early, the efficiency of the metal jet is greatly reduced, and it is easy to break.

This puts forward high requirements for the fuze, to be able to detonate at the best explosion height, and the precise touch is imminent. However, during World War II, most of the armor-piercing shells used were traditional mechanical fuses, which could not control the explosion height at all, so the armor-piercing power was very unsatisfactory.

Piezoelectric fuses can solve this problem. The so-called piezoelectric fuse is to install a piece of piezoelectric ceramic on the head of the missile body, which can generate a pulse current of nearly 10,000 volts under the impact of sufficient force, and use the current to detonate the electric detonator. It not only has enough reaction speed (not to mention the speed of the current), but also has a relatively high safety threshold to ensure that it will not detonate without sufficient impact force.

Speaking of which, comrades should also understand what the US imperialists are doing by welding so many "bird cages" and "anti-theft nets" for armored vehicles in Iraq and Afghanistan, right? In fact, its use is very simple, it is to deal with piezoelectric fuses.

There are two situations in which a rocket equipped with a piezoelectric fuse hits a "birdcage" and an "anti-theft net", one is that it is stuck with an iron bar, and after being stuck, the natural fuse will not work and will not detonate the armor-piercing projectile. The second situation is to hit the iron bar and explode, as mentioned earlier, the jet of the armor-piercing projectile is very sensitive to the explosion height, and the general "iron cage" is at a distance from the main armor, and without the optimal explosion height, the erosion of the jet on the main armor is naturally greatly reduced.

Improving the fuse is only the first trick, the second trick is to slide the cartridge, it is true that the sliding cartridge cannot completely solve the problem, but it can indeed be optimized. Some comrades may be asking again, in this case, why not use the technology of G-type armor-piercing shells?

The reason is very simple, the G-type armor-piercing bullet is both a ball and a bearing, and it also needs to be lubricated, with high technical requirements, average effect and high cost. Naturally, it was abandoned to create trouble with Soviet technology and not be able to mass produce it.

With the sliding cartridge belt, the D-5T can basically control the rotational speed of the armor-piercing projectile at about 8,000 rpm. It's a lot better than the original tens of thousands. Of course. There is also a problem with the use of sliding cartridges. In order for the plastic sliding belt to occupy a part of the space of the projectile body, it is necessary to reduce the diameter of the medicine cover in the projectile body. The size of the medicine cover is directly related to the depth of armor piercing, simply put, the larger the medicine cover, the stronger the armor piercing ability. However, this reasonable trade-off is also worth it, otherwise, even if the diameter of the medicine cover is large, but the rotation speed is too high, at most, the static armor piercing value is good. The actual battle is still a tear.

Of course, in order to make up for the regret of the reduction of the diameter of the medicine cover, Li Xiaofeng also prepared a third improvement measure, that is, to work on the medicine cover itself. The effect of armor-piercing ammo cover material on armor-piercing ability is also obvious. Only metals with high density and good ductility are suitable for medicine covers, such as the commonly used copper. Copper has good ductility and density, and is relatively inexpensive, making it suitable for large-scale use.

However, whether it is brass or copper, there is still a big difference compared to some other metals, such as gold, silver or tantalum. Of the three, gold is naturally the most desirable. Malleability is the best and the density is the highest, followed by tantalum. Again, silver.

Of course, silver is only as strong as copper, and the price does not reflect this strong advantage. So a certain immortal gave up silver in the first place. His focus is on gold and tantalum. Gold is familiar to everyone, a well-known precious metal, anyway, if the Military Commission knows that a certain immortal is going to use gold to make an armor-piercing bullet to attack the enemy, I am afraid that he will spray it to death with saliva, this is a real gold coin bullet.

So, obviously, gold is also not suitable. The end up is tantalum, which is slightly less dense than gold and is very malleable. Since World War II, it has been widely used in the capacitor and chemical industries as well as in the atomic energy industry. Later, the familiar terminal sensitive bullets or explosive forming ammunition are inseparable from tantalum.

In fact, Li Xiaofeng has long been eyeing the value of tantalum, and since 1930, he has developed tantalum ore to refine tantalum through North Industries, which is widely used in the field of communication manufacturing. This time, he was also forced by Tukhachevsky to use the tantalum cover.

Of course, it turns out that Li Xiaofeng's choice is very correct, how deep is the armor-piercing bullet that the D-5 was equipped with? It's less than 50 millimeters, which is basically the level of tickling the panther and the tiger. With the use of tantalum covers, the static armor penetration value is as high as 450 mm, and the dynamic breaking value can also reach the level of 150 mm to 180 mm. This makes it possible for the D-5 series to fire armor-piercing shells that can penetrate the frontal armor of the later improved Panther's hull. And this is certainly great news for the T-34-85.

However, having said that, tantalum medicine cover is good, but it is really not cheap, and in later generations, a kilogram of pure tantalum will cost three or four thousand yuan, which is a precious metal. Of course, for the Soviet Union, the biggest problem with the use of tantalum powder covers was not that it was expensive, but what about gold coin shells in order to defeat the enemy?

The key reason for restricting the large-scale use of tantalum powder covers in the Soviet Union is that the Soviet Union has very little tantalum and niobium ore, and the quality is very low, to put it bluntly, the Soviet Union does not have many tantalum resources. This precious metal is completely dependent on imports.

So what are the countries with the richest tantalum resources in the world? Sixty percent is in Australia, the remaining 30 percent is in Brazil, and the last less than 10 percent is left in the Soviet Union, which may not even have 0.01 percent.

For example, NORINCO's tantalum and niobium ore comes from Brazil, and the ore mined from Brazil is transported to Vyborg, Finland, where it is processed into refined tantalum. After the outbreak of the Great Patriotic War, because the Baltic Sea access to the sea was blocked, tantalum ore was transported to Murmansk, and then transported by rail to Vyborg for processing. To be honest, this cost is a bit high.

But there is no way to do it due to the high cost, who let the Soviet Union lack this? Moreover, tantalum is still very versatile and sophisticated, even if it is expensive. Moreover, Li Xiaofeng is also ready to use both hands, using the NVK-150 of tantalum alloy medicine cover as a high-end A cargo in small quantities, and distributing it to T-34-85 or SU-85 as a can opener, which is only used when encountering the likes of Black Panther and Tiger. At the lower end of the spectrum is the NVK-150A, which is a B cargo, which uses a copper medicine shield and has a less than inferior armor-piercing ability (around 100 to 120 mm).

Although the B cargo is not enough to destroy the improved Black Panthers, such as the Black Panther G and Black Panther F. But the problem of hunting tigers is not very big, as for the old-fashioned armor-piercing shells issued to D-5T, this is still a rest, whether it is AP or APCBC or APCR shells, D-5T basically cannot slaughter tigers and cheetahs from a safe distance. In that case, let's make do with armor-piercing bullets first!

And Li Xiaofeng also has an idea, why the Soviet Union's armor-piercing shells are like this, one is backward technology, and the other is that the production capacity demand is too great, thousands of SU-100 and tens of thousands of SU-85 and T-34-85 need a large number of armor-piercing bullets (I am afraid that it will take tens of thousands of rounds to accompany each vehicle with five rounds of APCR, calculating this number, can the Soviet Union afford to supply APCR with tungsten carbide cores?). In order for these tanks and tank destroyers to work, the USSR had to bite the bullet and supply armor-piercing shells, which would have to reduce the technical requirements and meet the tactical needs first.

If the D-5 can reduce the amount of armor-piercing ammunition used, with the industrial capacity of the Soviet Union, develop and produce better armor-piercing ammunition equipment for the high-end D-10 and D-25 series, the problem is not big. Anyway, there is no composite armor in this year, so it is okay to let the D-5 and F-34 use armor-piercing shells. What's more, armor-piercing shells have low technical requirements and are cheaper, which is suitable for the existence of a large number of T-34s...... (To be continued.) )

PS: Bow and thank the giants of giants, drunken maples, lazy readers, xxxxxxjj, Sayuka attack aircraft, Spirit of Jinling, Southern Wanderers and Comrade Juventus!