The shell flew over a mound of earth at a distance of 400 meters, creating a crater in the ground that was 30 centimeters deep. The iron ball at the bottom of the pit was still smoking.

"The ground here is still soft." Lin Shenhe took a look, "If the ground is hard enough, it can produce a jumping effect, and the power will be even greater." ”

Zhang Bolin began to pull the tape measure, from the 400-meter benchmark to the crater, and the actual measured distance was 460 meters.

"The range is passable." Lin Shenhe was satisfied, "The accuracy is quite satisfactory." ”

"Is that satisfying? Nothing! Ying Yu thinks it's unbelievable, just this accuracy? It's a cannon, and it's a point-and-shoot shot.

"That's right, the smoothbore gun is at that level. The enemy is in a dense formation, and this cannon can kill at least more than a dozen of them. ”

Then they fired more than a dozen rounds from different angles and charges, and the range ranged from 400 meters to 1,200 meters away. When the elevation angle reached a maximum of 45 degrees, the shell flew at a distance of 1500 meters. However, after the range exceeded 400 meters, the target was completely gone, and basically you could only look at the general direction, and a total of 4 mounds were hit in the whole process. The gun was red and hot, but the barrel was stable and there were no cracks. For the sake of safety, after fifteen shots, Lin Shenhe announced a ceasefire and switched to a new gun.

"Still fighting? I'm almost exhausted. "The artillerymen were all exhausted. Otherwise, the artillery reset after each fire is laborious. And there are always some problems with the direction angle after reset, and it has to be readjusted. The physical exertion is particularly high.

"I still have to go up and withdraw the gun, so I have to cut off the gas." Zhang Bolin was panting like a cow and almost collapsed to the ground.

"After the industrial department comes out of the spring," Lin Shenhe was also tired enough, "Don't think about it before that." ”

After the break, a test shot was carried out on the cannon cast in clay molds, and the firing range was slightly shorter than that of the cannons cast by the hard mold method. The performance is also not bad.

Subsequently, the artillery team used iron molds and the Rodman method to cast a variety of caliber guns, including 12-pounder howitzers, 12-pounder mountain howitzers, 12-pounder cannons, and on the basis of the experience of casting light artillery, began to cast 32-pounder cannons and 32-pounder naval guns for the navy (note: this is a direct-fire short cannon, invented and used by the British Navy). All of these guns were successful in the test firing, and the cannon roared and the smoke filled the vicinity of Lingao Corner all day long.

After accumulating sufficient casting experience, the artillery team designed an improved version of the Armstrong cannon with a threaded bolt based on the drawings and instructions of the Armstrong cannon in the database.

The rifled gun was no better than the smoothbore gun, and although the caliber of the cannon (cannon) had reached 120mm when the artillery group cast the 32-pounder cannon, the designers of the artillery group were careful to set the caliber of the first Armstrong cannon at 70mm.

The material of the gun was cast steel. It is no longer difficult to cast an already familiar artillery group. The main problem is the processing of rifling. In the arsenal, this requires special machines, at least special tooling. It's too late to build it right away, but fortunately, the traverser has predecessors who can be emulated - the military industrial soldiers of the Eighth Route Army and the New Fourth Army. They built rifles and artillery under the simplest mechanical equipment and manual conditions. By flipping through the materials, Zhan Wuya decided to imitate the local method used by Wu Yunduo to squeeze rifling jishu when he made flat-firing guns. That is, with an olive-shaped steel column, the circumference is engraved with concave and convex diagonal lines, and then the steel column is hard wedged into the body tube.

How this steel pillar is made, Wu Yunduo just said a rough idea, and there is no specific pattern. The artillery group summoned all the talents who knew about machinery and drawing, held consultations and studies overnight, and drew out the design drawings, which Jiang Ye was responsible for, first casting with sand and then using lathes to make steel molds.

A few days later, the barrel of the first Armstrong cannon had been processed, and the bolt was a little difficult, but with the joint efforts of Jiang Ye and Xiao Bailang, the threaded bolt was finally completed and successfully installed. After assembling and polishing the haode cannon, it looked smooth and slippery, and everyone looked at and touched, with a lewd look.

The shells were made of cast iron long-tipped solid shells, but the fuses of rifled guns were very difficult to solve.

Regardless of whether the fuse has a safety device or not, the basic structure is a spring-loaded pin type. This requires two things: ** and springs. Compared with the thundermercury used in **, the spring is a big problem they face. There is nothing difficult in the manufacture of springs themselves, it is rare to find materials - modern springs are generally made of alloy steel, which can not be produced with a small converter, and the mechanical group has a reserve of spring steel in its hands, but the cannonball tube is a consumable and cannot be made by using the material in reserve.

"How's the chemical fuse?" Zhang Bolin had a whim.

"How?"

"Use a chemical reaction to detonate the cannonball," Zhang Bolin's idea is very simple: use a small bottle of glass or porcelain, filled with a chemical, surrounded by another chemical that can react violently with it, when the cannonball is hit, the glass bottle shatters, and the two drugs are mixed together to react violently, detonating the ZHA drug 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 is broken?" ”

"Shipped separately. The fuse and shell are transported separately and loaded when they are needed. ”

Wang Luobin shook his head again and again: "This idea is good, but you have forgotten one point: the chamber pressure of the rear-loading rifled gun is much greater than that of the smoothbore gun, and the fuse must have sufficient strength, and the glass tube will definitely break at the moment of launch, and the result will be a blow-up." ”

Zhang Bolin was dumbfounded, he hadn't thought about this problem at all.

"How? Cannons aren't as easy to play as you think, are they? Ying Yu patted him on the shoulder.

"It's not impossible to use this on other explosives," Lin Shenhe said, "but the shells are definitely not okay." ”

"It seems that advanced artillery alone is not enough." Wang Luobin smiled bitterly. The flowering shell of the smoothbore cannon is not as difficult as jishu, but this jishu cannot be used on a rifled gun.

"Carbon steel can also be used to make springs." Jiang Ye thought for a long time, recalling that he seemed to have seen a spring of carbon steel.

"Yes, you can use 0.6% carbon steel. It's just that I don't know if the performance is enough. Ji Wusheng said, "You can try it, I'll check the book to see how the heat treatment is done." ”

"Can you do the heat treatment?" Zhan Wuya himself was not sure, so he used the heat treatment furnace to do some simple work.

"I'm not sure, I can only rely on checking books and shiyan."

"It's not easy, it's not something that can be done in a day or two."

Several people pondered for a long time without results, and Zuihou or Lin Shenhe proposed: since the first batch of Armstrong cannons equipped with Armstrong cannons is for the navy, the anti-ship is still mainly armor-piercing shells. Solid cast iron bullets are fine.

"What about carrying out shore bombardment missions?"

"With a mortar." Lin Shenhe said.

Mortars are the predecessor of mortars, and making jishu is much simpler than mortars, and the grenades used are also easy to make. The disadvantage is that the non-explosive rate of grenades is relatively high, and it can only be said that talking is better than nothing.

"How to solve the problem of lead plating?" Wang Luobin asked. Historically, the Armstrong cannon was kicked out of the battleship by the British Navy because of the casualties caused by the splashing of lead on the body of the cannon.

"I read the information that at that time, someone proposed that lead plating with electroplating would not cause this problem-" Wang Luobin said the solution he had mastered.

Early rifled artillery shells were jishu similar to Mini rifle shells, which used explosive gases to expand the bottom of the bullet and insert it into the rifling. Therefore, there must be a soft metal wrap on the outside of the projectile body, and lead is the most suitable metal. The problem arose - the combination between the cast iron projectile body and the lead jacket was difficult, especially in the absence of a hydraulic press, and the result was a flying lead skin like the Royal Navy's Armstrong gun.

"Electroplating is too extravagant right now, and it's not enough on jishu." Zhan Wuya said.

"There is a way of thinking, I don't know if it is feasible, it was used on the shells of the 3-inch Shenkl guns of the Americans."

Since the lead skin is easy to hurt people when it falls, and there is no way for them to stop it from falling, the best way is to change to something that will not hurt people if it splashes out.

Shenkl's shells are surrounded by papier-mache on the lower half of the shell, which is a belt made of concrete pulp, which has enough strength and toughness to penetrate the rifling without hurting people due to the fragmentation and flying off when discharged.

"Is this kind of coagulated pulp difficult?"

"In 1860, science and technology should not be difficult, it is nothing more than pulp and glue, which is not as easy to use as a ready-made recipe process, and can only rely on the experimenters."

"This task can be given to the chemical group, and they have experience in this."

As he was talking, He Ming from the military group suddenly broke in, with a serious face.

"What's wrong?" Wang Luobin felt a little bad.

"According to the captive's confession, the pirates will most likely attack us in the near future!" He said as he handed over a document, "This is a prisoner trial notice issued by the security team. ”