Hongli Mountain is located between the Fen River and the Lan River, just at the northern end of the delta, separated from Jingyou Town by only one Lan River.

When cleaning up the Du family, Qin Chuan didn't go to Hongli Mountain, mainly because of the lack of troops and the fact that he couldn't manage so many places.

After getting the title deed of the Du family, he took Song Zhiting to the Hongli Mountain Mine.

Originally, the scale of this mine was much larger than that of the Black Mountain Mine, and there were more than 1,000 miners, but the Du family had run a lot in the past few days, and now there are less than 600 people left, all of whom are honest.

There are less than 10,000 catties of pig iron left in the mine, and there is not even a single catty of wrought iron, which has long been taken away by the fugitive stewards and miners.

I knew that they could sell it for one or two or a half dollars of silver if they took a hundred catties of pig iron, and the price of wrought iron almost doubled.

Qin Chuan didn't bother to care about those pig irons, what he wanted was this mountain and the hundreds of honest miners.

The first thing he did was to pick 200 miners, pick out people from the Black Mountain Mine and the people of Lou Fan Zhuang, and gather enough 500 recruits, and some of them were dispersed and incorporated into the three battalions of Xiandeng, Wudang, and Trap, and then transferred 150 veterans from these three battalions to form a new battalion with 250 recruits, called Shifang Battalion, which means the Pure Land of Ten Directions, and Luo Ba served as the battalion officer and was stationed in Lou Fan Town.

Luo Daniu's first camp and Li Dingliang's trapping camp took turns to attack the three cliffs and the East Hulu River, and also took turns to return to Shentai Peak Dazhai to recuperate.

After the adjustment, Qin Chuan's Guan Emperor army had 1,500 troops, and the tiger and leopard battalion originally only had twenty-five Jiujishan old bandits.

There were not many miners in the Hongli Mountain Mine, and even fewer after being drawn to serve as soldiers, but Qin Chuan was not in a hurry to replenish the miners, and only handed over the mine to Song Zhiting to manage, so that he could only open a blast furnace and produce less iron, anyway, now he has too much pig iron to use up.

Yan Sanqi didn't come to Hongli Mountain, but only asked Qin Chuan to help him pick a dozen skilled furnaces to send to the Black Mountain Mine, where he was busy researching dry distillation kilns, improving blast furnaces and blowers.

As a result, when Qin Chuan was selecting a furnace in Hongli Mountain, he found that the side of the blast furnace was full of black things that looked like charcoal.

Take a closer look, hey, it's coke.

After asking, it turns out that Hongli Mountain is made of coke to make iron, and after careful questioning, it turns out that many mines in Datong Prefecture will dry distill coke and use coke to make iron.

Yan Sanqi, a southerner, is used to using charcoal in Fujian, so he doesn't understand the coke dry distillation method in the north.

I don't know why the Meng family doesn't use coke to make iron, it may be that Master Meng is rigid, or he doesn't want to increase the cost, so he spends manpower to make coke.

After learning that there was a dry distillation kiln in Hongli Mountain, Yan Sanqi hurried over, first went around in several dry distillation kilns for a long time, painted dozens of thick paintings, and then took a dozen furnaces and happily returned to Montenegro to dig the kiln.

In fact, Qin Chuan did not expect him to be able to smelt gray iron, the temperature of the blast furnace in this era should not exceed 1,300 degrees, even if coke is used, I am afraid it will not reach the temperature required to reduce silicon, and the possibility of refining high silica gray iron is very small.

However, this is scientific research and technological improvement, even if there is no success rate, Qin Chuan will also ask Yan Sanqi to try.

Even if you can't smelt gray iron, you can learn to use coke to make iron, you can increase the furnace temperature, and it is good to smelt molten iron with less impurities.

Chen Zhan is also building a blast furnace, built in the artillery factory in Mengjiazhuang, when the blast furnace has not yet dried, he began to make clay models, preparing to cast the iron molds of the two cannons first, and when the iron molds are cooled and polished, the blast furnace should also be usable.

Compared with the two who were still making preparations, Li Xuejing's progress was much faster, and he had already begun to flintlock the pistol.

This is because the iron used in the flintlock pistol does not need to wait for the newly smelted iron of Yan Sanqi, but only needs to repeatedly heat the wrought iron, carburize and forge it repeatedly, and beat 20 catties of wool iron into 4 catties of fine iron, which can be used to make the barrel.

Knowing that Li Xuejing was going to make a firecracker, Qin Chuan hurried back from Hongli Mountain and pointed fingers at him.

Chen Zhan and all the blacksmiths, apprentices, etc., came and gathered around to study.

Li Xuejing, who looked weak, personally went into battle, clamped a piece of iron, commanded the blacksmith to beat continuously, refined two iron bars, and beat them into long iron sheets, Li Xuejing took out a small three-foot-long iron core from the furnace, wrapped the iron sheet on the iron rod, and let the blacksmith continue to beat it repeatedly.

The iron core was coated with fine mud, which originally did not need to be heated, but Qin Chuan wanted to test the iron mold heating method on the barrel, so he preheated the iron core in advance.

It's just that the core is easy to bond with the barrel during forging, so the core must be rotated every time it is forged, and even pulled out to cool down.

After one layer of iron sheet is wrapped and forged, another layer of iron sheet is wrapped and the forging continues, so that the two layers of iron sheet, one hard and one soft, are fused together to form a firm barrel.

This is a double-layer composite gun-making method, compared with the three-stage welding method, the barrel produced by this method greatly reduces the explosion rate, and the barrel is much stronger.

But there is also a disadvantage, that is, it is impossible to make a barrel that is too long, and three feet is basically the limit.

The caliber of the forged barrel is smaller than the predetermined caliber, and it is necessary to use manpower to drill out the gun, which requires a drilling machine and a drill bit.

The drill bit is made of fallen steel, that is, filled steel, and the hardness and flexibility are enough, but the drill machine is made of wood and stone grinding, which is so simple that it cannot be described, and it takes a month to drill the gun pipe with this kind of drill machine.

Qin Chuan realized that if he wanted to develop guns, he had to study the boring machine first, and make sharp and durable drilling tools, preferably to make roller bearings.

Bearings are not difficult, ancient China had potterwheels very early, this thing is the ancestor of bearings, to the Yuan Dynasty there were cylindrical rolling armillary spheres, and now most mule carriages are equipped with bearings of wooden rollers.

It is not difficult to make iron pillar roller bearings with steel filling, first make several small iron pillars of the same size, inlay the iron pillar into an iron ring, close to the outside, and then inlay a small iron ring inside, clamp the iron pillar one inside and one outside, and wrap the edge and seal it, and add lubricating oil to become.

The challenge is how to unify the specifications.

The specifications of hand-made things are often uneven, and if the specifications cannot be uniform, they cannot be used on the boring machine at all, and the slightest deviation can make a barrel scrapped.

This thing has to be explored slowly.

Li Xuejing made five barrels in a row, and when the barrels cooled, he began to make spring steel, which was the biggest difficulty in making flintlock pistols, and it was also the main reason why Bi Maokang invented flintlock pistols in the eighth year of Chongzhen but could not be mass-produced.

When the ancient blacksmiths were making weapons, they found that the weapons that had been quenched at high temperatures and then tempered were the most durable, so there was spring steel.

However, spring steel, which has enough elastic power to knock flint out of sparks and ignite gunpowder, is not easy to forge.

The only way is to smash manpower and iron into it, and among the hundred steel bars, ten of them can meet the standard, and if they can be used on the flintlock pistol, Qin Chuan is very satisfied.

Anyway, he had manpower and iron.

For two days, Qin Chuan stayed in the fire gun factory, studying iron striking with Li Xuejing.

On the third day, he received good news: Wang Jizong wrote a letter to Shuntianfu to buy new grain seeds, which were escorted to the Haidart Bureau in Jingcheng Town, and transported to Lou Fu.

Qin Chuan immediately threw the matter of the fire gun factory to Li Xuejing, and happily took Wang Jizong out to greet him.

He has been looking forward to this batch of new grain for a long time, and tomorrow autumn, he will be able to eat corn cobs, roasted sweet potatoes and potato beef stew in Mengjiazhuang.

When I went out five miles away, I met the grain transportation team of the Zhenhai Dart Bureau, with about 200 people and more than ten mule carts.

Originally, only a few dozen stones of grain are not escorted by so many dart masters, and even the dart bureau rarely accepts this kind of small order, but the importance of this batch of seeds is self-evident, Wang Jizong asked a friend in Shuntianfu to open a high price of six hundred taels, and asked the Zhenhai Dart Bureau to send two hundred dart masters to escort it, so as not to be robbed by the bandits who are not long-sighted.

In the near future, the dart master of the Zhenhai Dart Bureau did not hand over the dart directly, but sent it to Mengjiazhuang, and refused Qin Chuan's kindness to invite them to dinner, accepted six hundred taels of silver, and asked Wang Jizong to sign and draw the pledge before leaving.

Qin Chuan stepped forward happily and counted them carefully one by one.