The shell flew over the mound of soil 400 meters away, creating a 30cm deep hole in the ground. The iron ball at the bottom of the hole was still emitting green smoke.
"The ground here is relatively soft." Lin Shenhe took a look and said, "If the ground is hard enough, it can produce a jumping effect, and the power will be even greater."
Zhang Bolin began to stretch the measuring tape, and from the 400-meter benchmark to the crater, the actual distance measured was 460 meters.
"The range is passable." Lin Shenhe felt satisfied, "The accuracy is quite satisfactory."
"Is this enough? Nothing was hit!" Ying Yu found it unbelievable. Such accuracy? This is a cannon, and it shoots directly.
"That's right, the smoothbore cannon is only at this level. The enemy is in a dense formation, and one shot can kill at least a dozen of them."
Then more than ten rounds were fired using different angles and charges, with the range ranging from 400 meters to 1,200 meters away. When the elevation angle reached the maximum 45 degrees, the shells flew 1,500 meters away. However, the range exceeded
After 400 meters, the accuracy was completely gone. Basically, I could only look in the general direction. A total of 4 mounds were hit in the whole process. The artillery became red and hot, but the barrel was very stable and there were no cracks. For safety reasons
For safety reasons, after firing fifteen times, Lin Shenhe declared a ceasefire and replaced the gun with another gun.
"Still fighting? I'm almost exhausted." The artillerymen were all so tired that they couldn't breathe. Others were fine. Resetting the artillery after each firing was laborious. And the direction and angle after reset were always a little bit different.
The problem is that we have to make adjustments again. The physical exertion is extremely high.
"We still have to go up and withdraw the gun, because we have to stop breathing." Zhang Bolin was panting like an ox and almost collapsed to the ground.
"Let's wait until the industrial sector comes out with the spring to withdraw the artillery." Lin Shenhe was also exhausted, "Don't think about it before then."
After the break, the cannon cast with clay molds was tested again. The range was slightly shorter than that of the cannons cast with hard molds. The performance was also pretty good.
Subsequently, the artillery team used iron molds and the Rodman method to cast artillery of various calibers, including 12-pound howitzers, 12-pound mountain howitzers, 12-pound cannons, etc. Based on the experience gained in casting light artillery, they began to cast naval
32-pound cannons and 32-pound naval guns. These various artillery pieces have all been successful in test firings. The sound of cannons was rumbling and the smoke was filled near Lingaojiao all day long.
After accumulating sufficient casting experience, the artillery team designed an improved version of the armstrong cannon using threaded gun bolts based on the drawings and instructions of the armstrong cannon in the database.
Rifled cannons are no better than smoothbore cannons. Although the caliber of the long gun (cannon) had already reached 120mm when the artillery team was casting the 32-pound cannon, the designers of the artillery team still cautiously set the caliber of the first armstrong cannon at 70mm.
The artillery is made of cast steel. Casting is no longer difficult for artillery teams who are already familiar with it. The main problem is the processing of rifling. In the arsenal, this requires special machines, or at least special tooling. It is too late to build it immediately.
Fortunately, the time travelers have predecessors they can imitate - the military and industrial soldiers of the Eighth Route Army and the New Fourth Army. They also made rifles and artillery under the simplest mechanical equipment and manual conditions. After reading the information, Zhan Wuya decided to imitate the ones made by Wu Yunduo.
An indigenous rifling technique used in flat-firing cannons. That is, an olive-shaped steel column is used, engraved with concave and convex diagonal lines on the circumference, and then the steel column is wedged hard into the barrel.
Wu Yunduo only gave a general outline of how to make this steel column without any specific drawings. The artillery team summoned all the talents who knew mechanics and drawings to hold discussions and research overnight, and drew up the design. Jiang Ye was in charge, and first used sand casting.
Cast, and then use a lathe to turn the steel mold out.
In the end, this extrusion method proved to be effective. A few days later, the barrel of the first armstrong cannon had been processed. The gun bolt was a little difficult, but with the joint efforts of Jiang Ye and Xiao Bailang,
The threaded gun bolt was finally completed and successfully installed. The assembled and polished cannon looked smooth and smooth, and everyone looked and touched it with lustful looks on their faces.
The artillery shells use long-pointed solid cast iron bullets, but the fuze of the rifled gun shells is very difficult to solve.
Regardless of whether the fuze has a safety device or not, the basic structure is a spring firing pin type. This requires two things: and a spring. Compared with the mercury fulminate used in the fuze, the spring is a big problem they face. The manufacturing of the spring itself is not difficult.
The rare thing is the material - modern springs are generally made of alloy steel, which cannot be produced with a small converter. The mechanical team has a reserve of spring steel, but the artillery tube is a consumable and cannot rely on the reserve.
Made of materials.
"How about chemical fuses?" Zhang Bolin suddenly thought.
"How to say?"
"Use chemical reactions to detonate artillery shells." Zhang Bolin's idea is very simple: use a glass or porcelain vial with a chemical inside, surrounded by another chemical that can react violently with it.
Medicine, when the cannonball is hit, the glass bottle shatters, and the two medicines mix and react violently, detonating the gunpowder in the cannonball.
"It's not very safe." Xiao Bailang said, "The shells have to be constantly moved and transported. What if the glass bottle breaks?"
"Transport separately. The fuses and shells are transported separately, and they are loaded when needed."
Wang Luobin shook his head repeatedly: "This idea is good, but you forgot one thing: the chamber pressure of the breech-loaded rifled cannon is much greater than that of the smoothbore cannon, and the fuze must have sufficient strength. The glass tube will definitely break at the moment of firing. As a result,
That’s it—explosion.”
Zhang Bolin was stunned, he had never thought about this problem at all.
"How's it going? Cannon isn't as easy to play as you thought, right?" Ying Yu patted him on the shoulder.
"It's not impossible to use this fuse on other explosives," Lin Shenhe said, "but it definitely can't be used on artillery shells."
"It seems that advanced cannons alone are not enough." Wang Luobin smiled bitterly. There is no technical difficulty in the smoothbore cannon's explosive ammunition, but this technology cannot be used on rifled cannons.
"Carbon steel can also be used as springs." Jiang Ye thought for a long time and recalled that he seemed to have seen carbon steel springs.
"Yes, you can use 0.6% carbon steel. I just don't know if the performance is enough." Ji Wusheng said, "You can give it a try. I'll check the book to see how heat treatment is done."
"Can you do the heat treatment work?" Zhan Wuya himself was not sure, so he did some simple work with the heat treatment furnace.
"I'm not sure either. I can only rely on reading books and experiments."
"This matter is probably not simple. It cannot be done in a day or two."
Several people thought hard for a long time with no results, and finally Lin Shenhe suggested: Since the first batch of armstrong cannons are for the navy, anti-ship missiles should still be based on armor-piercing bullets. Solid cast-iron bullets will be fine.
"What about a shore bombardment mission?"
"Use a mortar." Lin Shenhe said.
The mortar is the predecessor of the mortar. The manufacturing technology is much simpler than that of the mortar, and the grenade it is used with is also easy to make. The disadvantage is that the grenade has a relatively high non-explosion rate, which can only be said to be better than nothing.
"How to solve the problem of lead plating?" Wang Luobin asked. Historically, the Armstrong cannon was kicked out of the warship by the British Navy because of the casualties caused by the lead fragments flying from the projectile when the cannon was ejected from the chamber.
"I read the information and said that someone proposed to use electroplating to plate lead so that this problem would not occur -" Wang Luobin said the solution he had.
Early rifled artillery shells were based on technology similar to Mini rifle bullets, which used explosive gas to expand the bottom of the projectile and insert it into the rifling. Therefore, the outside of the projectile must be wrapped with a soft metal, and lead is the most suitable metal. The problem immediately arises
Come on - it is difficult to combine the cast iron projectile body and the lead skin, especially in the absence of a hydraulic press. The result of the forced combination is like the British Royal Navy's armstrong cannon, with the lead skin flying off.
"Electroplating is too luxurious right now, and the technology is not sufficient," Zhan Wuya said.
"There is an idea, I don't know if it is feasible. It was used in the shells of the Americans' 3-inch Shenkl gun."
Since the lead sheet could easily hurt people if it fell, and they had no way to prevent it from falling, the best way was to replace it with something that wouldn't hurt people if it splashed.
Shenkl's artillery shells are wrapped with papier-mache on the lower half of the artillery shell. This is a belt made of concrete pulp. It has enough strength and toughness to be embedded in the rifling, but will not be broken when it comes out.
It breaks and flies down and hurts people.
“Is this papier-mâché difficult?”
"Technology in 1860 shouldn't be difficult. It's just pulp and glue. There are no ready-made formulas and techniques to use. We can only rely on experimentalists."
"This task can be handed over to the chemical engineering team. They have experience in this."
While they were talking, He Ming from the military team suddenly barged in with a serious look on his face.
"What happened?" Wang Luobin felt a little bad.
"According to the prisoners' confessions, pirates are likely to launch an attack on us in the near future!" He said and handed over a document, "This is the prisoner interrogation notice issued by the security team."