Seeing Bai Yuan's crestfallen expression, Li Daoxuan chuckled to himself.
Ah. He's reached the stage where accuracy starts to matter.
This was inevitable.
From the moment firearms were invented, gunsmiths everywhere had been locked in a single, obsessive struggle: how to make the projectile go where you actually want it to go.
The transition from the clumsy three-eyed cannon to the bird-gun was already one such attempt—longer barrels, better balance, all meant to stabilize the shot as it left the muzzle.
But there was a hard limit.
A smoothbore gun, no matter how lovingly crafted, was still a smoothbore. Inside the barrel, the bullet bounced, skidded, and argued with physics before flying off in whatever direction it pleased. No craftsman could negotiate with that.
If you wanted a bullet to fly straight, there was only one solution:
Rifling.
Rifling wasn't some unreachable miracle. As early as 1498, German gunsmiths had figured it out. And now it was the Chongzhen era—1629. More than a century had passed. With Ming-era craftsmanship, rifled barrels were absolutely possible.
They were just slow, exhausting, and hard to mass-produce.
But since the technology itself was no longer the bottleneck, Li Daoxuan didn't hesitate.
He pulled out the technical materials he'd prepared long ago—and casually dropped them straight onto Bai Yuan's head.
What he provided was a straight-rifling design. Much easier than spiral rifling. You had to crawl before you ran.
Below, Bai Yuan was still holding his flintlock bird-gun, squinting at a bird startled into the sky.
Left aim.
Right aim.
Nothing felt right.
He sighed—and fired anyway.
Boom.
At the exact same moment, the enormous sheet of paper drifting down from above intersected the bullet's path.
The lead ball punched a neat hole right through the center of the diagram.
Bai Yuan nearly leapt out of his skin.
"Oh no! Disaster!"
"I shot the Heavenly Lord's scripture!"
The paper fluttered down in front of him. He stared.
It was clearly a method for improving firearm accuracy—but the most crucial part, the cross-section diagram of the rifling, was now gone. Shot clean through.
"Ahhhhh—!"
Bai Yuan screamed like the world was ending.
"It's over! Completely over! The Dao Xuan Tianzun personally bestowed a method to improve firearms—and I destroyed it! I destroyed the heavenly text! Aaaahhh!"
He collapsed face-first onto the ground.
The servants rushed over in panic and hauled him back up.
Bai Yuan clutched his head in despair.
"I don't even know how to atone for this. The 'rites' of the Six Arts—cross it out. Cross it out forever."
Above, Li Daoxuan burst out laughing.
He calmly printed another copy and dropped it down again.
Bai Yuan froze—then his spirit revived instantly.
"There's another copy?! So destroying one doesn't matter?!"
Hope restored, he spread the massive sheet out, climbed up a nearby tree, and stared down at it carefully.
After a long while—
He still didn't understand it.
The problem was simple: Bai Yuan had studied mathematics, but not physics or chemistry. Without those foundations, many of the subtler principles were opaque.
But not understanding wasn't a dealbreaker.
He immediately ordered the servants to roll up the "heavenly text," sprinted for the train station, waited for the next train, shoved the enormous paper roll into a carriage—
Clack-clack clack-clack—
—and headed straight for Gaojia Village School.
The school had become… unusual.
Next to the five-story teaching building stood a giant microscope. Students climbed to the fifth floor, crossed specially built platforms, and peered down through it, while others on the second floor placed specimens onto a raised tray below.
Beyond that were other oversized experimental devices, all positioned close to the building so students could climb up several stories to use them.
These massive instruments drastically accelerated students' understanding of physics—turning abstract ideas into something they could see.
Bai Yuan, however, had zero interest.
If it wasn't part of the Six Arts, it didn't exist to him.
He charged straight into the building and stormed into the library.
Inside, Song Yingxing and Young Master Bai were casually reading.
"Quick!" Bai Yuan barked to his servants. "Bring the heavenly text!"
The huge sheet was unfurled before them.
Young Master Bai understood immediately.
"So that's how it is. So that's how it is."
Bai Yuan already knew he couldn't compete with his son in these matters—and since physics didn't fall under "numbers" in the Six Arts, he didn't care in the slightest.
He grinned.
"So what does the heavenly text mean?"
Young Master Bai pointed at the rifling diagram.
"This stabilizes the bullet. Lead is soft—when fired, it deforms slightly. The deformed part presses into the grooves, preventing it from bouncing around inside the barrel. When it exits, it no longer flies randomly."
He paused, then added thoughtfully,
"Like a train wheel following tracks. The bullet follows the grooves. At least—that's how I understand it."
Song Yingxing nodded.
"Precisely. Your physical intuition is excellent."
Bai Yuan's eyes lit up.
"So once this 'rifling' is added, the bullet flies straight? Point at something, hit it?"
Both Song Yingxing and Young Master Bai nodded together.
"Yes."
Bai Yuan laughed loudly.
"Ha! Then how do we make it?"
Song Yingxing pointed to the sheet.
"The heavenly text explains it clearly. Heat the barrel red-hot, then use a specialized cutting tool to draw grooves inside. The key difficulty is maintaining perfectly even force—if the groove is uneven, the bullet won't fly straight."
Young Master Bai grinned.
"That's why you shouldn't pull it by hand. Human force always deviates. Even when it looks straight to the naked eye, under the microscope it's crooked. We've seen this many times."
Song Yingxing continued,
"So we should first build a wooden device—like a loom—with a straight guide rail. Mount the cutter on the rail. That way, stability is guaranteed."
The two of them brainstormed together.
Within minutes, a workable solution emerged.
Bai Yuan stood nearby, dumbfounded. He hadn't understood most of it.
But he understood one thing clearly:
Rifling could be made. Soon.
Delighted, he clapped Young Master Bai on the shoulder.
"Ha! You've really grown up. You can help me now."
"When I'm old and hand Bai Fortress over to you…"
"…there shouldn't be any problems, right? Hahahaha."
Footnotes & Trivia
[1] Rifling Before the Ming
Straight rifling existed in Europe by the late 15th century. Spiral rifling came later and offered better stability but was vastly harder to produce. Early straight grooves already represented a massive leap over smoothbores.
[2] Why Rifling Works (In Plain Terms)
A deformed lead bullet gripping grooves reduces random tumbling. Even without spin, consistent guidance dramatically improves accuracy—an insight often rediscovered independently across cultures.