Because Wang Dong asked, Zhao Yu made a technical briefing.

Although the propellant gives the warhead the energy to produce the effect, as the carrier of energy, it is also the agent that produces the striking effect, and the effect of the warhead on the elastic performance of the gun is comparable to that of the propellant, and after a bullet is determined, the warhead is the only variable that can affect the performance.

It's the same with the countersunk.

According to Zhao Yu, in fact, there is no need to subdivide the caliber of firearms according to combat use at all.

The advent of countersunk ammunition has made it possible to unify the caliber of firearms, at least to allow several firearms used by soldiers and the most equipped to use the same caliber.

If this is the case, the first to be eliminated is small-caliber rifle cartridges.

Born in the Vietnam War, the small-caliber rifle cartridge was developed for the special environment of the jungle and never replaced other bullets.

The point is that small-caliber rifle cartridges have serious performance flaws.

The US military has an extremely deep understanding of this.

It is precisely for this reason that the US special forces are equipped with rifles that fire 7.62mm NATO rounds, and many of these firearms have been launched by major firearms companies.

Small-caliber rifle cartridges have not been replaced, only because their portability is still irreplaceable.

Even without taking into account the weight of the firearm, replacing the SS109 with 7.62 mm NATO shells would reduce the number of bullets carried by the infantry by a third without increasing the weight of the infantry, while increasing the weight of the infantry by a few kilograms.

For the already overwhelmed infantry, these kilograms may well be the last straw that crushes the camel.

For example, in addition to carrying M4 carbines and M9 pistols, the infantry of the US mechanized infantry division also had to wear a body armor weighing at least five kilograms, a five-liter hump water bottle, a Kevlar helmet, a set of individual communications equipment, a first-aid kit and several bags of military rations, and counting the necessary magazines, bulk bullets, grenades, and multi-purpose daggers, and even if they did not carry additional equipment, the total weight would be as high as 35 kilograms. Because they had to carry extra equipment, such as bazookas and grenade launchers, as well as ammunition boxes for machine gunners, the U.S. infantry had to carry more than 45 kilograms and even as high as 50 kilograms.

What is this concept?

Let the infantrymen carry fifty kilograms on their backs and charge in the line of fire?

Not to mention that soldiers are mortals, even track and field athletes who rely on their physiness to eat can't run fast with a weight of fifty kilograms on their backs, let alone far.

Obviously, adding a few kilograms of dead weight that cannot be removed at any time, and putting infantry on the battlefield is tantamount to sending them to death.

It is precisely because of this that small-caliber rifle cartridges have never been withdrawn from the stage of war.

It's just that for countersunks, that's not a problem.

Among the three indicators that determine the caliber of the countersunk projectile, the most important, the most influential, or the decisive one is actually the diameter of the warhead and the cartridge.

As for the length of the cartridge, it doesn't matter much.

In this way, the quality and size of the cartridge can be adjusted by changing the length of the cartridge to meet different needs.

Put simply, shortening the length of the cartridge reduces the quality of the cartridge and meets the requirements for portability at the expense of some performance.

Of course, it is also possible to increase the elastic performance of the gun by increasing the length of the cartridge.

All in all, if carrying is the main indicator, then there is no need to develop a separate small-caliber rifle cartridge, just a cartridge with a shortened cartridge.

As for the versatility of the cartridge, it is not a problem at all.

According to Zhao Yu, versatility can be solved by design, there are not many technical problems, and there is certainly no problem in terms of reliability.

It is precisely for this reason that Zhao Yu advocated the abolition of small-caliber rifle cartridges and the development of a lightweight rifle cartridge on the basis of general-purpose rifle cartridges.

In this way, only two calibers of countersunk shells are needed.

With the advancement of technology, for example, the emergence of a certain low-cost material that can replace tungsten alloy, it may be possible to unify the caliber of general-purpose gun bullets and machine gun bullets.

In fact, this is also the reason why Textron did not develop small-caliber countersunk ammunition.

However, the 8mm countersunk bullet developed by Textron is close to the SS109 bullet in size and mass, but the performance is on par with the 7.62mm NATO bullet.

In Zhao Yu's words, this is a mouse's eye.

Quite simply, the performance of the 7.62mm NATO shell is not enough, so why should it be on par?

Because Textron's 8-millimeter countersunk bullet has been successfully developed and delivered to the troops for combat testing, it is difficult to improve the extreme performance of the gun bullet by technical means unless it is overturned and restarted, and then in a few years, this kind of bullet that the US military has high hopes for may lag behind.

In this regard, Zhao Yu suggested that on the basis of maintaining quality, the size of general-purpose guns and ammunition should be appropriately relaxed.

Of course, there are many ways to control the quality, such as reducing the charge, or using a lighter warhead, but this will inevitably lead to a decrease in performance.

The benefits, no less, are obvious.

The larger size gives the bullet more room for improvement.

If, someday, a way is found to increase the load-bearing capacity of the infantry, it will only be possible to increase the performance of the bullet without changing the size of the bullet by increasing the charge or by using a heavier bullet, and there will be no need to change the gun for this purpose.

Quite simply, bullets are matched to firearms by size, and have no necessarily relationship with quality.

It's just that Zhao Yu can't guess the caliber standard that the Huaxia military may use, and in his words, no one can guess.

It must be admitted that Zhao Yu is indeed a top arms expert, not only understanding firearms, but also looking to the future.

It's just that the limitations are also huge, that is, all he sees is technology.

"Small-caliber rifle ammunition still has to be done, so we will take Textron's 8mm countersunk bullet as a reference object to ensure that the main performance is on par with it, and it is best to exceed it by a small margin."

"Is this necessary?"

Wang Dong smiled and said, "I can't understand the techniques you said, but those generals in the Pentagon can understand them?" The US military equipment has used small-caliber rifle cartridges for decades, is it easy to get them to give up? If we can come up with a small-caliber rifle cartridge with decent performance, we will have a head start. It's just that you don't have to put too much effort into it, because our purpose is not to sign a contract with the U.S. military. ”

"You mean ......"

"During our partnership with BAE Systems, we just provided samples for BAE Systems to work on the OIC project. As for mass production in the future, it will definitely be in Saudi Arabia. If you can do what you say and develop a general-purpose bullet with good performance that can replace small-caliber rifle cartridges, I will find a way to convince the Saudi military to let the Saudi Army be the first to eat crabs and abandon small-caliber rifles altogether. ”

"In other words, focus on the development of universal gun cartridges and machine gun cartridges?"

Wang Dong nodded and said, "It's just that first come up with a detailed design plan for small-caliber bullets, and it's best to make some sample bullets for testing." ”

"Okay, I know what to do."

Zhao Yu agreed, and Wang Dong didn't talk nonsense, after all, it was Zhao Yu who had the final say on technology.