After having a rough idea about personal weapons, Hwang immediately moved on to the support artillery section.
Facing a blank sheet of paper, Hwang crossed his arms and muttered to himself.
"Considering the level of craftsmanship, we could be ambitious, but the other parts can't keep up... There are only a few things we can actually do."
Hwang then opened the book he had placed beside him and examined the lists.
"New siege weapons and cannons... We need to develop these, but we also need something that can more definitively instill fear in the enemy."
Hwang, lost in thought, tapped his fingers on the entries for new siege weapons and cannons.
The most famous among them were the new siege weapons and cannons. The actual combat records of these weapons were also significant. However, Hwang felt that the cost was insufficient.
"Before the year ends, we must show tangible results. The ministers won't sit still because of the budget, after all."
After pondering which support artillery would be best, Hwang finally came to a conclusion.
"Indeed, there's no other answer. The Bigeukjinchunrai. For the sea, we have the turtle ship; for the land, we have the Bigeukjinchunrai. It might be a cliché, but..."
Hwang straightened his back.
"It's the most impactful!"
After deciding on the Bigeukjinchunrai, Hwang fell into another dilemma.
"Will it be Mk.1, Mk.2, or perhaps Mk.2-1?"
The 'Mk.1,' 'Mk.2,' and 'Mk.2-1' that Hwang had labeled were distinguished based on how the Bigeukjinchunrai would explode.
* * *
The 'Mk.1' and 'Mk.2,' and even 'Mk.2-1' were things that had puzzled Hwang for a while in the 21st century.
The 'Mk.1' is the scene we generally see in dramas, where the gunpowder inside explodes, and the fragments from the broken iron shell and the triangular iron pieces (菱鐵, malm iron) spread out, killing the enemy.
The 'Mk.2' is designed so that when the fuse inside ignites, the gunpowder and triangular iron pieces are ejected through the hole where the gunpowder was loaded. Due to the position of the fuse, the Bigeukjinchunrai rotates, spraying flames and iron pieces in all directions, causing casualties.
The reason for the 'Mk.2' was that the burning speed of the black powder used in Joseon was slow, making it difficult to achieve an instantaneous explosion that would shatter the shell and spray fragments and flames in all directions. Instead, the hole through which the gunpowder was loaded would be sealed with a wooden plug, and the flames and iron pieces would be ejected through this hole. When Hwang first encountered this theory, he was skeptical.
"Why? The Bigeukjinchunrai has two holes, one for the fuse and one for the gunpowder and iron pieces. Why only one?"
Unable to find a clear answer to this question, Hwang simply remembered it as an interesting fact and forgot about it.
Later, when a real Bigeukjinchunrai was excavated and an exhibition was announced, Hwang, who had just quit his civil service job and was preparing the blacksmith shop, immediately went to the exhibition.
At the exhibition, Hwang circled around the glass wall protecting the excavated Bigeukjinchunrai, examining it closely. After a long time, Hwang stepped back.
"One problem is solved, but another arises?"
The problem Hwang solved was the 'lid iron' (開鐵, lid lock) issue. According to the records, after installing the fuse, the lid lock was used to cover it.
'How did they fix it without a special locking mechanism?'
Hwang's question was answered when he saw the real Bigeukjinchunrai. The lid part was square-shaped, with a round hole in the center for the fuse. The square part had a long groove on the wall. Thus, after placing the lid lock, turning it 90 degrees would lock it into the groove. Solving one problem, another arose: the hole for loading gunpowder and iron pieces was smaller than expected.
In various restoration diagrams, the triangular iron pieces were quite large. The CG shown at the exhibition solved this by inserting the iron pieces through the fuse hole and loading only gunpowder through the side hole.
'That way, the fragments won't spread evenly... That's really...'
To resolve this question, Hwang diligently searched the internet. A video he found on the internet added to his confusion.
The appearance of 'Mk.2-1.' The video was from the early 2000s, broadcast by a TV station.
A professor from a naval research institution appeared, explaining that the triangular iron pieces and gunpowder were loaded through the fuse hole, the fuse was inserted, and the lid lock was placed. After that, a lead plate was inserted into the gap between the body of the Bigeukjinchunrai and the lid lock, and hammered in to secure the lid.
In the subsequent firepower test, the Bigeukjinchunrai ejected fragments from the lid lock area and was left empty. The body of the Bigeukjinchunrai, now empty, showed almost no damage.
Ultimately, Hwang, still unable to resolve his questions, decided to solve them himself, and the result was the demonstration at the back of the blacksmith shop that made his cousin grab him by the collar.
Recalling his tumultuous memories from the 21st century, Hwang, who was pondering whether to go with Mk.1, Mk.2, or Mk.2-1, shook his head vigorously and picked up the gold pen.
"Why should I even worry about this? If we're going to make it, let's go with Mk.21! The 21st-century version!"
Hwang's choice was to maximize productivity and lethality.
* * *
Watching the ministers debate the etymology, Choe Hae-san spoke up.
"This Bigeukjinchunrai is a device that the Crown Prince planned and designed himself."
At Choe Hae-san's explanation, the attention of Sejong and the ministers focused on Hwang. With the attention on him, Hwang confidently declared,
"His Majesty will not be disappointed."
Sejong, with a proud expression, responded to Hwang's words.
"You've never disappointed me before. General, proceed."
"Yes, Your Majesty. First, the structure of the Bigeukjinchunrai is such that it is filled with gunpowder inside the shell. When the fuse is lit, it explodes. It may look simple, but it contains a very ingenious mechanism."
"Ingenious mechanism?"
"It can control the explosion time."
Choe Hae-san explained the usage of the Bigeukjinchunrai.
"Wrap the fuse around the wooden tube and insert it into the fuse hole, then load it into the Bigeukjinchunrai and cover the lid. Next, fill the side hole with gunpowder and seal it. After that, place it in the large cannon and fire. It will fly 300 paces (about 360m) to 500 paces (about 600m) and then explode."
Sejong asked, intrigued by Choe Hae-san's explanation.
"Does wrapping the fuse around the wooden tube control the time?"
"Yes, Your Majesty."
"Power?"
"We will demonstrate it now. Fire!"
At Choe Hae-san's command, soldiers brought a large cannon and the Bigeukjinchunrai to the demonstration area. Stopping in front of Sejong, the soldiers placed everything down and performed a military salute.
"Chung!"
After the salute, the soldiers moved the large cannon and the Bigeukjinchunrai to the center of the demonstration area. The cannon's muzzle was aimed at an open field about 100 jang (about 330m) away on Mokmyeoksan Mountain. The field was already filled with densely packed dummies wearing red and blue target boards, chain mail, and other armor.
The soldiers who set up the large cannon prepared the Bigeukjinchunrai. They inserted the wooden tube with the fuse, covered it with the lid, and tightly sealed it with a specialized tool. Similarly, they filled the side hole with gunpowder and sealed it with the same tool.
After preparing the Bigeukjinchunrai, the soldiers loaded it into the large cannon. They then pulled the firing mechanism at the back of the cannon, inserted the ignition cap, and pulled the string, hiding behind a protective wall.
"Your Majesty, please take cover for a moment. This is to prevent any unforeseen danger."
"Understood."
At Choe Hae-san's words, Sejong and the ministers took cover behind the protective wall set up in front of the platform. Once Sejong was safely covered, a military official standing next to Choe Hae-san waved a large red flag.
"Fire! Fire! Fire!"
Bang! Whizz! Boom!
As the soldiers hiding behind the protective wall pulled the string, the large cannon fired the Bigeukjinchunrai. It flew through the air with a whistling sound and landed in the open field, exploding with a loud noise.
"Ugh!"
Sejong let out a small groan as the shockwave from the explosion hit him.
"Your Majesty! Is everything alright?"
Sejong, who was groaning, was urgently asked by Hwang, who was standing right next to him.
"It's nothing. I was just startled."
"Your Majesty, you can stand up now."
"Grunt!"
As Sejong stood up, putting strength into his thighs, Hwang muttered to himself.
"Indeed, you need to lose some weight... Should I reduce your meal portions?"
He muttered this in a low voice, but Sejong seemed to hear it and shouted at Hwang.
"You brat! Are you trying to starve your father?"
"No, no, Your Majesty! Please look at the target!"
Hwang quickly changed the subject, and Sejong, muttering a complaint under his breath, turned his head.
"Wow..."
Sejong and the ministers, who turned their heads to look at the target, were speechless.
Even from a distance, the targets and dummies set up around the open field were in a mess.
"Shall we go closer to see?"
"Of course!"
Curious, Sejong was the first to step forward and walked briskly.
* * *
"Good grief..."
"This is the power of one shell..."
The ministers, who arrived at the dummies, could not hide their shock.
Not a single dummy was standing upright. The poles that held the target boards were scattered everywhere along with the boards, and the dummies wearing armor were similarly scattered.
Sejong and the ministers picked up the fallen target boards and dummies to examine their condition.
"Wow..."
"If these were real people... I don't even want to think about it."
"If these were real people... it would have been hell."
Seeing the target boards and armor riddled with holes, the ministers shook their heads.
As they said, if this weapon were used on real people in armor, it would have been a terrifying situation.
"If anyone survived this, it might be more merciful to kill them," Sejong muttered, looking at the target board in his hand. The board in Sejong's hand had a large hole that could fit a fist.
Not all the ministers had negative reactions. Jo Mal-saeng, who was in charge of military affairs, lost his composure.
"Your Highness! Crown Prince! Is it possible to mass-produce this shell immediately? No, please say it's possible!"
"Well, with a bit of effort...," Hwang replied.
At Hwang's answer, Jo Mal-saeng immediately prostrated himself before Sejong.
"Your Majesty! We must mass-produce this shell immediately! While the long gun and the horseback gun are ingenious weapons, compared to this shell, they are just minor aids!
If we can mass-produce this shell, the Jurchen problem can be solved immediately! Not just the Jurchen, but we can also completely subdue the detestable Daimado! No, not just Daimado, but we can even eliminate the main base of the Japanese pirates!"
"Hmm..."
"Your Majesty! We must mass-produce it!"
"Hmm..."
Jo Mal-saeng, shouting as if his throat would burst, made Sejong look intrigued. However, Sejong decided to take a step back.
"We've confirmed its power, so let's gather more detailed information and make a decision. It could be a burden on our capabilities."
"Your Majesty! If our capabilities are lacking, we can improve them! If we lack the foundation, we will search every kitchen and outhouse in Joseon! If we lack sulfur, we will trade illegally to obtain it! If we lack charcoal, we will cut down every tree in Joseon! We must mass-produce it!"
Jo Mal-saeng seemed ready to grab Sejong's pants and beg. Huang Hee interjected.
"Minister! Did you not hear His Majesty's words? He said to gather more information and discuss it! Why are you in such a hurry? Get up! This is disgraceful!"
"Grunt..."
Hearing Huang Hee's reprimand, Jo Mal-saeng straightened his body and looked at Sejong. Seeing Jo Mal-saeng's earnest expression, Hwang muttered to himself,
'Why does that cat from the movie come to mind?'
* * *
"Explain why the Bigeukjinchunrai has such power."
"Yes, Your Majesty."
At Sejong's command, Choe Hae-san began his explanation.
- The shell of the shell is made as thin as possible. It is strong enough to withstand the impact of firing and landing but not strong enough to withstand the internal explosion.
- Inside the shell, small iron balls are also placed. These balls increase the number of fragments, enhancing its lethality.
- The power of the gunpowder was increased. While not using explosive oil or armor-piercing gunpowder, the process of mixing soil with the gunpowder was omitted to maintain its power.
"Truly, the effort is evident."
At Sejong's evaluation, Choe Hae-san bowed and replied.
"The effort was mainly in adjusting the thickness of the shell. The rest followed the decisions already made by the Crown Prince."
In Choe Hae-san's answer, Sejong's gaze on Hwang was filled with many thoughts. After looking at Hwang, Sejong asked Choe Hae-san,
"Just now, the Minister of Military Affairs requested mass production of the Bigeukjinchunrai. Is it possible?"
"Based on the supply of gunpowder, I believe it is possible."
At Choe Hae-san's answer, Huang Hee interjected.
"General, is it really possible? Earlier, the Crown Prince mentioned that the lack of skilled craftsmen made mass production of armor-piercing gunpowder impossible. Based on my knowledge, to mass-produce such a powerful shell, many skilled craftsmen would be needed. Wouldn't the same problem arise?"
Hearing Huang Hee's point, Choe Hae-san nodded.
"The minister's point is valid. However, when the Crown Prince designed this shell, he also considered this issue."