After seeing the process of the six bronze and red-coated cannons and metal mold casting barrels newly cast by the Tongzhou Gun Factory, Emperor Chongzhen specially convened Sun Chengzong, Li Banghua, Bi Maokang, Sun Yuanhua, Sun Heding, and Liu Han in the newly completed Second Hall of the Armed Forces Institute to hold a pre-imperial meeting on the development and production of firearms. Pen, fun, pavilion www. biquge。 info

Now, after more than half a year of hard work in the Tongzhou Gun Factory, Tang Ruowang, Xiong Sanba and other Westerners have taught the casting process of bronze artillery to the craftsmen and technicians of the Ming Dynasty.

Moreover, they used the clay fan one-time casting bronze artillery technology, which is not much different from the traditional clay casting technology of the Ming Dynasty, and after more than a dozen repeated trial casting, it can be said that they have successfully cultivated a group of artillery craftsmen who have mastered the art of making the fan.

In the future, Tang Ruowang and Xiong Sanba will naturally continue to serve in the Tongzhou Artillery Factory, led by Sun Heding, along the current technical ideas, continue to cast various types of bronze or brass artillery for the Ming army, such as the large bronze red-coated cannon, which naturally needs to continue to be cast, and will be used as a weapon to defend the city in the future.

But for them, the direction of Tongzhou Gun Factory's future efforts is mainly to cast small and medium-sized bronze guns that are more needed at present, that is, field guns that can be installed on gun carriages with wheels and transferred to battle with the army in the field.

The technique of bronze artillery casting has been relatively mature, and the next step is mainly to work the lightness, portability and mule and horse of the bronze Hongyi cannon, and cast more small and medium-sized models of field bronze artillery.

At the same time, Emperor Chongzhen also issued an order again, asking Bi Maokang, Sun Yuanhua and others to select skilled Ming cannon craftsmen from Tongzhou Cannon Factory to go to Baiye City in Zunhua, and open another secret cannon factory in the iron factory area of Baiye City, specializing in the casting process of cast iron artillery and even cast steel artillery.

Today's Baiye City, about 50,000 catties of refined iron and 8,000 catties of low-carbon steel output per month, in addition to the production of cold weapons and equipment such as knives, guns, arrows, and armor, there is completely spare power to cast iron cannons.

At this meeting, Emperor Chongzhen told Li Banghua, Bi Maokang and Sun Yuanhua the concept of Tiefan Casting Cannon, and asked them to conduct experiments in the Baiyecheng Cannon Factory, and also told the two of them to keep the secret of Tiefan Casting Cannon, whether it was before the success of the trial casting, or after the successful trial casting, he and his craftsmen were not allowed to disclose the ideas and techniques of the Tiefan Casting Cannon to Western gun technicians and any outsiders.

Bi Maokang and Sun Yuanhua, who had seen the production of clay fan casting cannons and molten core barrels, had suddenly lit up in front of them since they heard the words Tiefan casting cannons, and suddenly there was a feeling of opening up.

Because the defects of the clay fan are determined by the clay and mud quality of the clay fan itself, if it is converted to an iron model of uniform specifications, will it overcome the defects of the clay fan?! This is the question that Sun Yuanhua quickly thought of after hearing the emperor put forward the words "Tie Fan Casting Cannon".

In fact, whether it is a bronze cannon cast with a clay fan, or a cast iron cannon with a clay fan, these technologies are not uncommon in the Ming Dynasty.

Because the cost of casting copper cannons is relatively high, many artillery pieces in the Ming Dynasty are made of iron, such as thunderbolt cannons, tiger squat cannons, and general cannons, many of which are iron cannons.

The mud fan casting cannon itself is not difficult for the craftsmen of the Ming Dynasty at all, after all, even the craftsmen of the Ming Dynasty can cast such a difficult top-level thing as the Yongle Bell.

If you don't know the relationship between the length and caliber of the Hongyi cannon, that is, the problem of double diameter, then most of the guns cast in a daze will explode.

As early as the late 14th century, the Ming Dynasty's musket and artillery casting was still at the forefront of the world, but in the early 17th century, it had fallen behind.

Especially after Ming Chengzu Zhu Di moved the capital to Beijing, the iron cannon casting process of the Ming Dynasty began to stagnate because of various factors, and in the middle and late Ming Dynasty, many of the artillery cast by Ming craftsmen were not cast in one piece or cast at one time, and most of them were spliced.

For example, the tiger squat cannon widely equipped on the nine sides of the Ming Dynasty has a casting method that is completely like a hoop barrel, which is forged and spliced by several pieces of cast iron, and the air tightness is very poor.

Among them, there is also the problem of mud fan, because the mud fan casting process is adopted, and the cannon is cast in one piece, the inner wall of the gun chamber is uneven, and there are many honeycomb-shaped pores, and the gunpowder cannot be far away if it is used less, and once it is used too much, it will blow up the chamber, which is completely a chicken rib-like existence.

Therefore, the craftsmen of the middle and late Ming Dynasty gave up the casting process of one-piece casting. In the future, once the iron fan casting technology is adopted, then the disadvantages and defects of the clay fan, such as high cost, long time, honeycomb holes, and the inability to scale and batch the problem, can be solved at once.

Emperor Chongzhen told Li Banghua, Bi Maokang, Sun Yuanhua and others the principle of iron fan casting cannons, and then told them the principles of casting muskets.

It is also divided into two groups, one group is dominated by the Portuguese gun technician Rodriguez, who continues to cast muskets for the Ming army in the Tongzhou Gun Factory, and the other group is all Ming craftsmen, who use the iron fan casting method to study and cast Western front-loading flintlock smoothbore guns.

The biggest problem in the production of muskets is the qualified barrel, some of the barrels are directly cast with molten iron directly on the clay fan made in advance, such as the thunderbolt cannon that Daming himself can produce, this kind of barrel is thick and short, the firing range is also short, and it is relatively heavy, no one can operate it, it looks very scary, but in fact the power is not great, even if there is more equipment, there is no combat effectiveness.

Some barrels are forged, that is, they are rolled into the shape of a barrel with a piece of wrought iron, and then put on an anvil made of tool steel, and then forged repeatedly.

There is also a barrel that, like the Tiger Squat Cannon, is made using the skills of a cooper. These barrels are either stubby and short, like a small cannon, and the range is too short to be powerful; Either it is long enough, but it is thin enough, but the air tightness is not good, and it is not resistant to high temperatures.

Of course, the musket barrels produced by these manufacturing methods cannot be compared with the barrels made by lathes directly on round steel of various diameters.

But in general, the metal core casting method demonstrated by Rodriguez can be used for large-scale production with a little modification.

Because the barrel of the artillery itself is also a tube, the principle of casting the barrel is the same as the casting barrel, the difference is mainly that the iron mold of the core of the cast gun is coarse, the wall is thicker, and the corresponding iron mold of the casting barrel is much smaller.

Moreover, casting the barrel with an iron mold does not need to melt the bronze core in the middle of the barrel by heating, as demonstrated by Rodriguez et al.

It is only necessary to brush one or two layers of high-temperature resistant fine clay slurry on the iron mold of the pipe core, soak it in water and soften it after casting and cooling, and then break the thin layer of clay slurry before the core and the pipe body, and extract the iron mold of the core.

Although the quality is certainly not as good as that of melt core casting, it is better that Tiefan can be used repeatedly, and cast iron barrels can be manufactured quickly and on a large scale, and once the problem of the barrel is solved, then as long as there is no problem with the supply of steel, large-scale musket manufacturing will not be a problem.

Now, once the supply of steel has come up, once a set of mature iron casting processes has been explored, then it is possible to manufacture cast iron running and cast steel cannons on a large scale, and it is also possible to cast a suitable barrel.

The difficulty of casting iron fan cannon, of course, is also difficult in making the model, first of all, the inverted mold method and the lost wax method to cast a unified standard of iron fan.

The next process, the same as the mud casting method, is just on the core of the iron fan and the barrel shell iron fan, brush one or two layers of high temperature resistant fine mud, after drying, the molten iron or molten steel, one time cast in the gap between the core and the shell, so that it can be cast into an iron cannon.

Compared with the clay fan, the biggest advantage of the iron fan casting method is that the iron fan can be used repeatedly, a set of iron fan can be used thousands of times, and the caliber and diameter of the cannon manufactured are convenient for the unification, standardization and standardization of artillery packages and projectiles.

Other than that, there is not much difference between the two in terms of casting process and procedure.

Of course, the difference between the iron fan and the clay fan, if it is not too big for a cast artillery, then for a barrel that is cast together, the difference is too big.

Naturally, the clay fan can't make the caliber size that a normal barrel requires, but the iron fan can easily do this, and it won't break, and it can be used repeatedly, so it won't be a problem to make barrels of various calibers.

After saying this in one breath, Emperor Chongzhen looked at Sun Chengzong, Li Banghua and the others with shocked expressions, and continued: "In addition to trying to use the iron fan to cast muskets and artillery, the production of other firearms materials cannot be left behind. I also have another idea here, that is, the gunpowder and projectiles used in muskets and artillery of various calibers should also be unified in weight and size, and the gunpowder should be made into a uniform amount of gunpowder in advance, and it can be directly disassembled and poured in when loading, and the size of the projectile should also be unified, and the medicine bag can be made of waterproof oiled paper or flammable silk, in short, whether it is a future artillery or a musket, the amount of gunpowder used each time should be unified in specifications, weights and standards, and made into a medicine bag in advance for later use. ”

Sun Chengzong, Li Banghua, Bi Maokang, Sun Yuanhua and others naturally hurriedly accepted the order.

In the seventeenth century, the dosage of muskets and artillery in Western countries has begun to gradually move towards quantification and standardization, but in the Ming army, standardization is still a rarity, a mature gunner or musketeer, its greatest ability, is to be able to calculate the pressure in the chamber according to the caliber and length of the artillery, and then selectively use gunpowder and projectiles.

This was already a standardized thing in the West at that time, but in the Ming Dynasty at that time, it was an untold secret of gunsmiths.

Emperor Chongzhen spent a morning almost all of his time in the Arsenal and its gun factory, and after secret talks with Li Banghua, Bi Maokang, Sun Yuanhua and others, Emperor Chongzhen came out to meet with Tang Ruowang, Xiong Sanba, and Rodriguez and other Westerners, and also met with the Ming craftsmen and technicians who performed well in the process of casting cannons, and everyone gave rewards.

After all these things should be done, Emperor Chongzhen first drove back to the lecture hall, and after having lunch with the students in the lecture hall again, he drove out of Tongzhou, ended this trip to Tongzhou, and returned to Beijing along the way with a large number of entourage.