In the Taiyuan defense battle two years ago, Li Yanqing annihilated more than 40,000 Jin soldiers siege with full preparation and sharp thunder, creating the first great victory in the Song and Jin war.

Later, Wang Ding took over the Taiyuan defense and followed Li Yanqing's defensive ideas, which also prevented the Jin soldiers from conquering Taiyuan City for several months, and the Jin soldiers also suffered heavy losses.

The Jin soldiers finally captured Taiyuan City, but they still attacked at night, using the power of the thunder to explode the city gate and finally captured Taiyuan City.

As a lesson from the past, Li Yanqing must beware. When he returned from the warehouse, Li Yanqing immediately came to the Taiyuan Military Equipment Field. This was actually the military armor building center established by the Jin Dynasty. In addition to Yanshan Prefecture, there was one place in Daming Prefecture and Taiyuan Prefecture.

About 300 craftsmen working in the military weapon field, all of whom were official weapons craftsmen of the Song Dynasty, with about 400 people building swords and guns and making armor here. After the Song army captured Taiyuan, these weapons craftsmen turned to serve the Song army, but they worked harder. The entire military weapon field was in full swing, giving a vibrant scene.

At present, the military weapon field is under the responsibility of Hao Wu, the supervisor of Jingzhao firearms who followed Li Yanqing's army. Hao Wu is Hao Er, and his brother is named Hao Wen. The two brothers have followed Li Yanqing for many years and are the core figures in the manufacturing and research of firearms.

"How is your brother's progress in developing a musket?" Li Yanqing asked with a smile.

Since Li Yanqing handed over the task of developing a musket to Hao Da three years ago, Hao Da has almost immersed himself in the research and development of a musket, and has failed countless times, but he still persevered.

Hao Wu smiled bitterly and said, "The last time the general proposed to use bamboo tubes to make the gun body, it has been successful, but its practicality is too poor and it will be destroyed at most twice. My brother decided to use pig iron or cooked copper to make it. The gunpowder has been successful. The gunpowder can be replaced by burning drugs that shook the sky. The key is the forging of the gun body. It was originally a fusion of two semicircles into a cylinder, but it will still crack after using it for more than a dozen times."

"Then why not use the method of Zhentian Lei sand mold to cast copper pipes at one time?"

The shell of Zhentian Lei is cast at one time. First, use coarse sand to make two inner and outer molds, pour copper water between the two molds, and then smash the sand mold to obtain a complete shell of Zhentian Lei. This technology is mature. The Gunpowder Bureau of Lin'an Prefecture and Jingzhao Prefecture can make more than 100 shells every day. Hao Dahao and Hao Er are the founder of Zhentian Lei, so it is impossible not to know this method.

Hao Er explained: "This method was used later, but the thickness of the copper tube shell was uneven and there were many impurities, which was easy to explode. A craftsman's left eye was blown blind. So now he changed to forging pig iron sheets, repeatedly forging to remove the impurities, then bent it into a tubular shape, poured with iron and melted it on the joints. However, the idea is very good, but there will always be unexpected problems in advance, but the problems are constantly being solved and are almost successful."

Li Yanqing nodded with a smile, "I am looking forward to the first musket coming soon."

As the two of them said, they soon walked into the military yard, which covers an area of ​​200 acres and is divided into five large yards. In the middle is the main warehouse, and there are five workshops around the main warehouse. If you look down from the sky, the layout is like a five-petal flower.

Li Yanqing and Hao Wen passed through the crossbow courtyard. The manufacturing of god-arm crossbows and military crossbows in the crossbow courtyard was suspended. More than 100 craftsmen were working hard to make trench machines. The wide yard was neatly placed with forty semi-finished products of heavy trench machines.

It takes at least two years to make a good catapult. The process is to make a throwing rod. It is usually made of long bamboo sticks, wrapped in three pieces with cloth, then soaked in oil and dried. Repeat more than ten times, and then brushed with ten paint and dried again. It takes two years to complete the production of a throwing rod. The made rod is extremely tough and difficult to break.

Fortunately, after more than 200 catapults in Taiyuan City were destroyed by the Jin soldiers, the poles were retained by craftsmen. Now, just build a shelf with a giant wood and install a pole and use it. It can be completed in a few days to make hundreds of heavy catapults.

"Sun Jiangtou, how many catapults are there now?" Hao Wu walked up and asked an old man with a smile.

The old man turned around and saw Li Yanqing. He hurriedly stepped forward and knelt down to salute. Li Yanqing smiled and waved his hand, "Manager Sun, please give up the gift, tell me about the current progress?"

Manager Sun stood up and said, "Now it is the third batch of catapults. Eighty-years have been made in the first two batches. Wang Zhengzhi has taken it to inspect it. This batch will be completed in two days. At that time, there will be one hundred and twenty catapults. Our goal is to build two hundred to ensure that there are fifty on each side of the city."

Li Yanqing smiled and said, "There are more than a dozen more aircraft to be added as a replacement."

"Please rest assured that in addition to repairing crossbows, we are all working hard to build catapults. We also have two particularly long throwing poles and are ready to build two super giant catapults with a range of 500 steps, which is sufficiently deterrent to the Jin soldiers."

Li Yanqing suddenly remembered the three largest catapults in Tokyo, which played a huge role. Unfortunately, the Song army could not move it when they retreated to the inner city, so they poured tinder oil and burned it. Thinking of this incident, Li Yanqing was quite regretful. Now this kind of super catapult may appear again, which really made Li Yanqing interested. He hurriedly said: "The super giant catapult you mentioned is very important, and we must start manufacturing as soon as possible."

"The villain understands, let's start preparing materials today."

After patrolling the crossbow field, Li Yanqing came to the main warehouse. He did not find any thunder when inspecting the warehouse outside the city. Later, he learned that the firearms of the Jin soldiers were stored in the warehouse of the military weapon field, but there were no gunpowder craftsmen in Taiyuan Prefecture, and the firearms stored were delivered from outside.

Hao Wu took Li Yanqing to the warehouse, and to the northeast corner of the warehouse, and opened a small iron door, "Report to the commander, the Jin soldiers' thunderstorms are all here, there are 325 in total!"

When Li Yanqing walked into the room, he felt that the room was gloomy and the light was very dark, but it was still dry. There were dozens of rows of iron racks in the wide room, and hundreds of dark thunder were neatly placed on it.

"This is not our thunderclap!"

Li Yanqing recognized at a glance that these thunders were different from the Song army's thunders. They had a round appearance and had different shapes of the mouth. It was obviously the thunders cast by the Jin people themselves.

"This is the second generation of Jin Kingdom's shocking sky!"

Hao Wu said with a smile that he was the number one expert in the sky-shaking thunder, and knew all kinds of sky-shaking thunders. He smiled and explained to Li Yanqing: "In the past, the sky-shaking thunders of the Jin soldiers inherited the Liao Kingdom and also learned from Xixia. Not to mention the crudeness, the thunders are very serious. At least half of the ten sky-shaking thunders were dumb thunders, and they were thin-skinned and the explosion was not very powerful. Later, the Jin Kingdom imitated our sky-shaking thunders. It is now, the structure inside is very similar, and the success rate has also increased. After experimenting with Beizhi, ten can explode seven, but the power is still half of ours."

"Why does this happen?" Li Yanqing asked in confusion.

"The reason is still the same as before. The Jin soldiers did not master the formula for burning gunpowder. The gunpowder in the Dazzling Thunder could not be fully burned. Our iron shell was too thick, so their gunpowder could not be blown up. They had to use thin shells or even ceramic shells, and of course the power would be much weaker. Moreover, there was no fuse fixture inside. If it was thrown, it would easily cause the fuse to deviate after landing, which would turn into dumb thunder. And if the fuse was too short, it would explode in the air in advance. This is why the Jin soldiers did not use the Dazzling Thunder to throw."

Li Yanqing pondered for a moment and said, "But when Taiyuan was captured by the Jin soldiers, the Jin soldiers used the thunder to explode the city gate."

"If they can't blow up the Taiyuan city gate with their own thunder, they must have used our thunder."
Chapter completed!