"Congratulations...... Congratulations to Mr. Cao, the catapult built ...... The construction is complete. Ma Jun said excitedly.

Cao Liang nodded, his joy overflowing.

Next, there will be testing.

The test is the last and most important link, and the success of the catapult is closely related to the test results.

At the bottom of this catapult, four huge wooden wheels are installed, which makes this catapult no longer a dead object fixed in place, but can move forward, backward, left and right, greatly increasing its maneuverability.

Ma Jun also took a lot of effort in the design of the wheels, extremely exquisite, not to mention the catapult up to several zhang of size, but only seven or eight people, you can easily push the catapult into the designated attack position, and you can also easily adjust the angle of shooting.

The construction site is very large, a few hundred steps ahead, Ma Jun has arranged for the handymen to build a stone wall, the stone wall is as high as a zhang, a foot wide, very strong, even if the strength of dozens of strong men is gathered, it cannot be easily shaken, let alone knocked down.

Ma Jun instructed Zhuang Ding to push the catapult to a place about 150 steps away from the stone wall and stopped.

One hundred and fifty steps is a distance that is difficult for bows and arrows to reach, even if it is an ordinary bed crossbow, the longest range is difficult to reach one hundred and fifty steps, so in siege operations, one hundred and fifty steps can be regarded as a safe distance, and the catapult is placed in this position, and the means of attack on the city are beyond reach.

In the past, ordinary trebuchets had a relatively short range, and they had to be pushed within a hundred steps of the city, so that the trebuchet would be easily exposed to the range of the enemy's long-range strikes.

This equipped catapult has no such worries at all, and can be arranged as you like.

The farmers pushed carts to transport the stone bullets.

In the past, most of the stones used in trebuchets were irregular blocks, mostly made of local materials, which had the advantage of being convenient and fast, but the disadvantages were also obvious.

Each time the stones thrown are different in shape, different sizes, and the weight is difficult to grasp, the accuracy of shooting is naturally difficult to control, and whether the thrown stones can hit the target is more of a kind of luck in addition to relying on the experience of the gunner.

If you are lucky, you will hit with one shot, but if you are unlucky, you will not be able to hit the side by throwing a dozen bullets in a row.

Cao Liang took the initiative to chisel the stones into a ball of equal diameter, so that the weight of the stone projectiles thrown each time was the same, so that it was easy for the gunner to operate and adjust to achieve the best shooting effect.

Moreover, the flight trajectory of spherical objects is the most ideal, and the air resistance is also the lowest, compared with irregular stones, it is not at the same level at all.

Of course, making stone bullets is a time-consuming and laborious projectile, a stonemason can only chisel three or five stone bullets in a day's work, and this is still rough processing, if you pursue fine lines and perfect spheres, I am afraid that you will not be able to make even one a day.

Some people think that making stone bullets is too wasteful, whether it is stones, stone bullets, after all, it is thrown out to smash people and walls, and the spherical stone bullets are beautiful and beautiful, but they are time-consuming and laborious to make, and the efficiency seems to be poor.

But Cao Liang insisted on his own approach, although it is more laborious to make stone bullets, but it is very beneficial to improve the shooting accuracy of catapults, for example, if you use stones, you can shoot one out of ten, and if you use stone bullets, you can at least reach one of three guns, and the attack efficiency can completely make up for the production efficiency.

Moreover, the stone projectiles of the same weight and specifications are convenient for the gunner to adjust, and the hit rate of the first few guns is often not good, but after the gunner's adjustment, the hit rate can be greatly improved, and it is not difficult to reach more than 90 percent.

Due to the different weights and shapes of the stones, it is difficult for the gunner to improve the hit rate even if he adjusts it.

So in the long run, stone bullets will become the standard equipment of counterweight catapults, and irregular stones will eventually be eliminated.

The weight of each stone projectile is the same, the size of a basin, and it weighs three and a half stones (about 52 kilograms).

With such a heavy stone bullet, it is more laborious for one person to pick it up.

The stone bullet was placed in the iron nest at the end of the throwing arm, and Ma Jun ordered the two Zhuang Ding to shake the winch and pull up the weight box.

The counterweight box is the centerpiece of the whole catapult, which contains several tons of stones, which are tightly tied around it with thick iron chains. The lifting of the weight box is the use of a winch, which can be operated by only two people to lift the weight box to the required height.

The firing principle of the counterweight catapult is to use the lever force generated by the sharp fall of the counterweight box to make the throwing arm rise and throw the stone projectile at the end of the throwing arm.

The heavier the counterweight, the faster it falls, the greater the leverage force generated, and the farther the projectile will be thrown.

The operation of the whole catapult only requires a few people, which is a stark contrast to the previous human-drawn trebuchet, which used to require hundreds of people to work together to complete the task, but now it has become simple and easy.

The first stone bullet roared out, but it did not hit the target, it flew over the stone wall, and fell to the ground dozens of steps behind the stone wall, with a loud bang.

Everyone couldn't help but show regret on their faces, but Cao Liang and Ma Jun didn't care, it was normal for the first bullet to not hit.

After intense adjustment, the second bomb was launched, and only a few steps away from the stone wall, it fell.

Although it didn't hit the target, the adjustment worked very well, and it was very close.

After adjusting again, Ma Jun waved his gesture, and the stone bullet roared out again, there was no accident, the stone bullet really smashed on the stone wall, the huge impact force made the stone bullet shatter into several pieces, the stone chips flew sideways, the rumbling sound was like thunder, the stone wall was crumbling, several stones on it were smashed away, and where the stone bullet hit, a huge pit obviously appeared.

Everyone was stunned, the power of this catapult is really amazing, that section of the stone wall that dozens of people can't shake, and a stone bullet is about to fall apart.

The catapult shot one after another, two bullets in a row, all of which accurately hit the position where the stone wall was hit before, especially after the last bullet hit the stone wall, the stone wall that was several feet long could no longer withstand such a huge impact and collapsed.