Europa Universalis 1867: Start by inheriting an armory

Abel rolled a heavy cylindrical steel cylinder out from under the test bench. It was a sealed chamber made from a single piece of Richard Chromium Nickel Special Steel, with walls up to four inches thick and an outer surface polished to an impeccable smoothness.

At the bottom of the cylinder is a precision piston channel, and below the piston is a small pure copper cylinder, its dimensions ground down to be exactly the same, with a tolerance of less than one-thousandth of an inch.

"This is one of the most dangerous experiments ever conducted by humankind," Abel said cautiously as he pushed it into the blast chamber and stood it up. "The high-pressure gas flow from the explosion of gunpowder in the chamber will drive the piston and instantly flatten the copper cylinder. What we need to measure is the degree to which the copper cylinder is flattened, so as to calculate the chamber pressure."

Thomas took out the brown flask containing the powder in the proportions A, C, and D, and carefully weighed the powder in the flask with a precision mechanical balance, taking fifty grams of each powder.

Then, using a horn spoon, I scooped the powder into a ceramic mortar and stirred it gently to make it more even.

Abel took out a neatly tied bundle of medicinal threads from another drawer, with a thin, platinum detonating wire containing mercury fulminate thread threaded through the center.

Mercury fulminate is the most sensitive detonator; it only requires a single electric spark to ignite and release all its energy along with the entire sample.

He inserted the fuse into the bottom of the chamber, used a long pair of tweezers to fix the end of the detonating wire to the center of the powder pile, and slowly poured in the powder of ratio A.

Thomas took a threaded steel plug from the tool rack and, together with Richard, screwed it into the threaded hole at the top of the chamber.

The steel plug was unusually heavy, with tightly interlocking threads, requiring all of one's strength to press down for each turn.

Abel applied a layer of yellow tallow to the joint between the steel plug and the cylinder wall, then took out a lead washer and placed it on the base of the steel plug to ensure an absolute airtight seal.

The last three people quickly retreated behind the glass window of the explosion-proof room.

"Ready?" Abel looked at Richard and Thomas beside him.

Richard nodded, covering his ears with his hands like a child about to set off fireworks.

Abel turned the electric spring handle in his hand, and the high voltage in the Leyden jar surged into the detonating wire through the copper wire, causing an electric spark to flash at the bottom of the chamber.

Ding!

A sharp, short metallic whistle rang out, as if someone were gripping a claw hammer and hammering away with all their might at an iron nail.

The three of them instinctively hunched their shoulders as their hearing slowly returned.

Abel and Thomas exchanged a glance. They didn't need to look at the bronze pillar; just hearing the voice made them frown.

That wasn't the burning they wanted; it was an explosion.

Thomas stepped forward to tighten the steel plug, which was held very tightly by the high-pressure gas. He grabbed the wrench with one hand in each hand and pressed down several times until the threads loosened.

He removed the steel plug, took a pair of long-handled pliers, and used them to pull out the thin piece of brass that had been severely deformed by the piston.

The edges of the copper sheet were cracked, like a wildflower that was withering and being trampled flat.

He measured it with calipers and shook his head: "Less than two millimeters. The gas release rate is too fast, which is far beyond the chamber pressure of forty tons."

Abel sighed, picked up a pen from the lab bench, and drew a line in the column for proportion A.

Richard pondered Thomas's conclusion that his chromium-nickel steel cannon barrel could easily withstand such chamber pressure.

But cannons are not disposable. A cannon has to fire hundreds of shells on the battlefield, and each shot inflicts an invisible heavy blow on the inner wall of the barrel.

If you want a cannon to fire harder and farther, simply increasing the chamber pressure won't work.

Imagine you want to push a heavy car very fast. In the old days, the method was to smash the back of the car with a giant sledgehammer. But the result was often that the car didn't move, and the back of the car was smashed first.

What he needs is a uniform and continuous thrust, and smokeless powder has such a combustion curve and a gradual peak chamber pressure.

But the A ratio was clearly not what he wanted.

Thomas took a clean cotton cloth from the drawer and gently wiped the inner wall of the chamber. He then threw the cloth into the waste bin and picked up the C-ratio medicine bottle from the lab bench.

He skillfully filled the chamber with the powder, plugged the fuse, tightened the steel plug, and retreated behind the explosion-proof window.

Abel took a handkerchief out of his pocket and wiped the sweat from his forehead.

"Let's pray that this reaction won't be too violent," he said.

He turned the crank, the spring clicked, and the Leyden jar discharged electricity.

This time, a dull and prolonged hissing sound came from inside the tube.

It was definitely the sound of burning, but it was burning too slowly.

Gas was squeezed out from the gaps at the bottom of the chamber, and a buzzing echo could even be heard inside the steel cylinder.

Without hesitation, Abel crossed out another line in the C ratio column.

Thomas went up and tightened the steel plug.

This time it wasn't so tight; he loosened it after twisting it twice.

He used pliers to pull the bronze pillar from the bottom of the chamber. The pillar was flattened by less than 0.5 millimeters and its surface was blackened by the incompletely burned nitrocellulose.

Thomas placed the bronze pillar on the velvet cloth and pushed it with his fingertips. The pillar did not roll, and its bottom surface was uneven.

"There's too much nitrocellulose in this ratio." Thomas breathed steadily, but his voice betrayed his disappointment. "The acetone didn't completely gel it, causing stratification during combustion. The outer layer burned out before the inner layer ignited, resulting in uneven gas release."

Abel stepped forward, held the bronze pillar up to the light, and examined it: "The chamber pressure and detonation velocity are too slow; the bullet can't even be pushed out of the barrel."

Richard stood behind them, reached out, and made a swipe between their shoulders: "It's okay, we still have sample D."

Abel looked at him and chuckled softly, "May God bless us."

Thomas then cleaned the chamber again, picked up the D-ratio medicine bottle from the test bench, filled the chamber, plugged in the medicine line, tightened the steel stopper, and put on the lead gasket.

The three people jogged back behind the blast-proof window.

Abel gripped the wind-up handle tightly, took a deep breath, and as the electric sparks flew, the explosion occurred as expected.

boom!

A deep, crisp explosion came from inside the steel cylinder. Its strong penetrating power made the glass instruments on the test bench tremble slightly, and several empty beakers gently collided on the shelf, making a soft tinkling sound.

Abel's eyes lit up immediately. Without waiting for anyone to react, he put on asbestos gloves, went to the side of the chamber, grabbed the wrench with both hands, and forcefully unscrewed the steel plug.

The moment the threads loosened, a wisp of gray smoke drifted out from the gap, carrying the smell of scorching gunpowder.

He leaned close to the entrance of the chest chamber and peered inside.

The inner wall of the chamber was as smooth as a mirror, without any black sulfur residue or traces of high-temperature burning.

Thomas came over with vernier calipers and long-handled tweezers and carefully removed the bronze pillar, which had been pressed into a mushroom shape, from the bottom of the chamber.

He placed the bronze pillar on the velvet cloth, measured it several times with calipers, and squinted at the markings on the caliper.

Abel stood behind him with his hands behind his back, not urging him.

Richard also entered the bomb shelter, his breathing slowing down as he went.

Finally, Thomas straightened up, placed the vernier calipers on the table, and faced Abel and Richard: "Fantastic! The degree of deformation proves that the asymptotic pressure of the sample is locked at twenty tons per square inch!"