51. Explosion, explosion, explosion.

The blast furnace was finally ignited. After lying dormant for half a year, Furnace No. 3 was revived under Song Yingsheng’s command. The cleaning process took two full days. Song Yingsheng was meticulous, crawling into the furnace chamber to inspect every crack without overlooking a single one. Only after confirming the furnace was in good condition and required no repairs did he officially declare the commencement of work.

The first batch of iron ore from Dongshan Mine had arrived.

“This is truly fine material. I’ve never seen ore this pure,” Song Yingsheng remarked, scooping a handful of iron ore and powder from a basket, watching the refined ore trickle through his fingers with admiration.

Yang Fan thought to himself, of course—it was magnetically separated ore powder, not just handpicked lumps as in other ironworks. How could it be anything but excellent?

The grade of iron ore directly determined the quality of the wrought iron produced. In this era, there was little understanding of phosphorus and sulfur removal; most methods were passed down orally as folk remedies, their principles unknown but their effects undeniable. Superior ore grade meant significantly better iron ingots.

“Let’s first smelt a batch of iron ingots with this ore to forge gun barrels for the divine rifles. Once the iron quality stabilizes, we’ll start casting cannons.”

“How are gun barrels made?” Yang Fan asked.

“First, the iron is melted continuously until the molten iron turns white-hot. At that stage, it’s poured into molds to form wrought iron ingots,” Song Yingsheng explained. “Then, a solid iron rod is used as a core, wrapped with softened wrought iron, and hammered into a tubular shape. Once formed, the core rod is withdrawn while the iron is still hot. After cooling, the inner wall is gradually bored smooth and even. One end is sealed, and the gun barrel is complete.”

Yang Fan thought that was incredibly complicated. Only master craftsmen could handle such work—apprentices certainly couldn’t. Even shaping iron into a perfect cylinder was beyond novices.

“How many people in the factory can do this?” Yang Fan inquired.

“Only five master craftsmen,” Zhao Fu replied. “Only Fu Laoliu can polish and bore the inner wall.”

“How many barrels can they make a day?” Yang Fan asked, though he was losing hope.

The group exchanged shocked glances.

“Sir, it takes at least a month to make a single gun barrel—it just can’t be sped up,” Fu Laoliu said with a grim expression.

As the lead craftsman, he was the one to report this.

The master was upset but powerless; if it couldn’t be done, it couldn’t.

Boring the interior was extremely difficult—entirely experience-based because the inside couldn’t be seen. Any mistake would cause the barrel to rupture upon firing, ruining the piece.

The barrel was a meter long.

Yang Fan felt frustrated—this pace was unacceptable. The Hundred House Guard station was in grave danger; they couldn’t wait that long.

Did they really have to hand out spearheads and send them to fight the bandits? That would be a massacre.

“Can gun barrels be cast?” Yang Fan asked Song Yingsheng.

“I’ve never heard of casting gun barrels. Probably not possible,” Song pondered.

“However, there used to be cast divine rifles, though technically, those weren’t matchlock guns,” he added. “But their quality was inferior, and they were prone to bursting. Rifles fire far more frequently than cannons, so the strength requirements are higher.”

“If you want to increase strength, the barrel must be made thicker, making the muzzle too heavy. Coupled with a long shaft, soldiers can’t wield it effectively. An unwieldy weapon is worse than useless—it would be a liability on the battlefield,” Song continued. “Think about it—if such a good concept hadn’t been widely adopted, there must be a reason. I’ve only read about the Nine-Jointed Divine Rifle in books. Why would border troops prefer the cumbersome triple-barreled matchlock over a nine-shot Nine-Jointed Divine Rifle?”

“If cannons can be cast, why not barrels?” Yang Fan struggled to understand. Smaller barrels should be easier to cast. A whole row of molds could produce dozens at once. It would only take a few days.

“I’ve never cast gun barrels. We can try. Our iron quality is excellent; maybe the cast barrels won’t burst,” Song said.

***

When the first batch of molten iron was ready and the molds completed, Yang Fan saw the casting molds for the first time.

They were quite simple: a carpenter first carved a wooden model of a gun barrel, drilled a hole to match the caliber, and filled it with sand. Then the wooden model was encased in clay, leaving an opening. After drying, the mold was ready.

Molten iron was poured through the opening. The iron burned away the wood inside, and after cooling, the clay was smashed off to reveal the hollow barrel. The sand inside was then removed, completing the barrel, although the interior still needed some smoothing.

“Furnace is open!” came a shout as the molten iron was poured sequentially into thirty molds.

The clay shells steamed and flared with flames shooting out from the pouring holes. The clay quickly glowed red-hot, and the factory temperature soared.

Yang Fan stood at the front line, watching intently. These divine rifles were his first products. Though simple in technology, they were crucial to Xinghe Ironworks.

By evening, the first batch of barrels had cooled.

Electric carbide lamps Yang Fan had purchased lit up the workshop brightly, though a faint pungent odor lingered in the air.

Song Yingsheng was fascinated by these lamps that ignited by adding water to small chunks. He had spent half the previous night studying them.

“Open the molds!” Fu Laoliu commanded. Two strong apprentices swung large hammers to break the clay molds.

Yang Fan picked up a barrel and examined it closely. The surface was smooth and finely crafted—the masters were indeed skilled, the clay molds delicate and polished.

The barrel felt heavy—surely a blow to the head would be fatal.

The apprentices began removing sand from inside.

The caliber was quite large—15 millimeters.

Yang Fan didn’t know that this was actually a small caliber.

At this time, the finest matchlock in Europe was Spain’s musket—a pinnacle of matchlock technology.

It had a 23mm caliber, weighed 10 to 11 kilograms, bullets weighed about 50 grams, with a maximum range of 250 meters and an effective range of 100 meters. It employed mechanical sights and fired two rounds per minute.

Though cumbersome, often requiring a forked rest to fire, its lead balls were powerful enough to penetrate heavy knight armor at 100 meters.

In this era, most firearms were ineffective beyond 80 meters.

The Spanish had conquered the vast and backward Inca Empire with such weapons.

Yang Fan’s “three-purpose divine rifle” was actually the most primitive form of a fire lance, not even a true matchlock—only one generation more advanced than those used during the Southern Song and Yuan dynasties.

Loading required a fuse and a fire striker.

No trigger mechanism existed.

“All cleaned out and the interior polished a bit,” Fu Laoliu reported.

“Let’s test it,” Yang Fan said.

***

They loaded the barrel with gunpowder, tamped it down with a wooden mallet and soft wood rod, then wrapped a lead ball in cowhide and rammed it in firmly.

“Everyone move behind that brick wall,” Song Yingsheng ordered.

The gun was fixed onto a sturdy hardwood block, aimed at a thick wooden target fifteen meters away.

“Fire!” Song commanded.

A fourteen-year-old apprentice lit the fuse with a fire striker and quickly dropped behind cover.

Bang! The gun discharged, a plume of white smoke billowing from the muzzle.

No explosion—Yang Fan’s heart leapt with excitement.

“Bullseye!” Fu Laoliu ran to check the target. The bullet had hit dead center. The long barrel allowed full combustion of powder, resulting in sustained acceleration. The bullet penetrated more than ten centimeters into the target.

If such precision and power existed on the battlefield, armor penetration would be assured.

But this was fired from a heavy, fixed wooden mount. A soldier’s hand couldn’t be so steady, and real combat distances wouldn’t be as short as fifteen meters—thirty meters or more was realistic.

At longer range, the effect would diminish.

Loading multiple charges in sequence meant the front shots had shorter travel and incomplete powder burn, drastically reducing power.

“Try loading two rounds,” Song said.

The craftsmen reloaded, this time with two charges.

Bang! The first shot fired; the apprentice immediately lit the second fuse.

Bang! The second shot fired.

“Excellent. No barrel burst and no ignition of subsequent charges,” Yang Fan said excitedly.

Next, they tested loading three rounds.

Bang! Bang!

On the third shot, a loud explosion shattered the barrel.

The apprentice lay flat, uninjured but pale with fright.

Song Yingsheng’s expression darkened: three rounds and it burst! This barrel was unusable.

There must have been cracks and air bubbles inside.

But this was only one barrel tested, so it wasn’t conclusive. After discussing with Yang Fan, they decided to test all thirty barrels.

That evening, Yang Fan received the test results.

All thirty barrels burst.

Five barrels survived seven shots; fifteen barrels lasted five shots; the rest fewer than five.

Casting gun barrels was a complete failure.