In the previous chapter, we talked about sniper rifles, and now we talk about bullets, the reason why Jiang Chen chose this Western-made 7.62mmX51mm bullet instead of the Soviet-style 7.62mmX39mm bullet commonly used in our country is for a reason, because the 7.62mmX51mm bullet has more advantages than the Soviet-style 7.62mmX39mm bullet, the 7.62mmX51mm bullet has more charge, the warhead is heavier, and it will shoot farther and more accurately under the same conditions. At that time, our country's bullet system has always followed the Soviet standard, and due to the lack of copper in our country, at that time, we went to Africa to build railways for copper mines.

In order to solve this problem, a steel shell and steel core bullet appeared. Although this kind of bullet is very cheap, but there is a fatal shortcoming, we all know that the reason why copper shell bullets are used is because copper has good ductility, so when fired, due to the effect of chamber pressure, the cartridge shell expands and closes to the gun wall, so that the bullet is shot very accurately and far away, while the steel shell bullet cannot reach this point because it is an iron cartridge case.

To be precise, the 7.62 mm bullet does not mean that the diameter of the bullet body or warhead is 7.62 mm, but that the caliber of the gun used with the bullet is 7.62 mm, and the maximum diameter of the bullet is slightly larger than 7.62 mm, which has an exclusive term called "interference" If you have the opportunity to see the warhead that has been shot, you will see a very clear indentation on the warhead, which is caused by the initial rifling extrusion of the bullet when the bullet is running in the chamber, and the projectile itself can form a "rifling effect", so that the bullet can produce enough self-rotation in the smoothbore, which is also unnecessary, and will also greatly increase the cost of bullet manufacturing, and far from the rifling through the barrel (more durable) and smooth, The mechanism of warhead or de-spin stabilization with uniform mass is reasonable. And the diameter at the bottom of the indentation is the diameter of the barrel. All rifled weapons, whether guns or rifled guns, have specially processed rifling inside their body barrels, of which the spiral convex part is called yang rifling, and the concave part is called yin rifling. The diameter of all rifled weapons is the diameter corresponding to the rifling in the rifle, and the diameter corresponding to the rifling is slightly larger than the diameter of the weapon, and the maximum diameter of the bullet or shell projectile is consistent with the rifling.

And Jiang Chen produced this kind of 7.62mmX51mm copper shell wrapped lead bullet, this bullet has excellent stability, very suitable for sniper rifle use, at the beginning the workers and leaders in the factory did not understand, why do we have to design and make bullets, with our original is not very good, we have to use this kind of copper shell bullet, but also require such a high process, now the production of one such bullet is equivalent to the production of ten original bullets required funds and time, but under Jiang Chen's strong insistence or production, but not more than tens of thousands of rounds, for experiments, they want to test this bullet and the original bullet to get the data comparisonto prove that there is no need for this. Of course, the best test results prove Jiang Chen's persistence.

The real test began, the first test of whether the gun can fire bullets smoothly, that is, reliability, this work of course fell on the shoulders of Ma Jun and Dongzi, Jiang Chen was originally opposed, the new gun test, it is very dangerous, although the remote safety test has been tried before, to put it bluntly, it is to pull the bolt with a line from a distance, so that even if the chamber is blown up, it will not hurt anyone. But now if he wants to go up, even if Jiang Chen is sure of these guns, but he is not calm about his friends and brothers, in case 、、、 Jiang Chen will feel guilty for a lifetime, but after their insistence and the agreement of the factory leaders, especially the fathers of the two, according to their words, everyone is raised by their father and mother, and they can't afford this danger, as the factory leader must lead by example, so they still let their children rush to the front.

However, there is still the softest side in the hearts of tough guys, this is not night, the father of the two, Director Ma and Deputy Director Zhang came to Jiang Chen's side one after another, chatting about some trivial and embarrassing things of their children, such as smashing someone's glass, stealing someone's watermelon, or fighting with someone's children, telling about their growth, Jiang Chen persuaded several times, but they still insisted, just kept asking about the performance of this gun, and analyzed the safety of this weapon with their knowledge, Jiang Chen could only comfort slowly, he couldn't guarantee whether this gun would not have problems, this was impossible, it could only be avoided and reduced, and now everything is ready, whether it will be achieved depends on the will of God.

"Are you two ready?" Jiang Chen asked in the cafeteria, Lao Wang Tou knew that these two people were going to test the danger of firearms, and the red oil tofu brain and fried dough sticks specially made for the two of them were definitely the top breakfast in this era.

"Don't worry, Brother Chen, we're all ready, don't worry, we have confidence in your gun. Dongzi said while eating the tofu brain in the bowl, this was the fifth bowl he had eaten, but he still didn't seem to be full, so he shouted to the old king: "Uncle Wang, is there anything else, another bowl!"

Jiang Chen was a little speechless, he said with black lines on his forehead: "Eat mine, I can't finish eating." ”

"Brother Chen, aren't you eating?" Dongzi wondered.

"I can't eat it, I can't eat it. "Jiang Chen has no appetite today, he really can't eat.

"Then don't waste it, it's all mine. After speaking, he took Jiang Chen's share and the fritters next to Jiang Chen, and stuffed them again.

Ma Jun on the side didn't eat less, but he didn't have such a rice bucket as Dongzi, and he also ate three or four bowls, he looked at Jiang Chen with a worried look and comforted: "Chenzi, don't worry, we have confidence in you." ”

Looking at Ma Jun's sincere appearance, Jiang Chen nodded heavily. The test finally began, Jiang Chen and the others came to the test site, and now the entire test site has been cleaned up, but there are still some people watching from the side, Jiang Chen ignored them and walked to the corresponding position.

"Are you ready?" Jiang Chen shouted loudly.

"Ready. On the test position in front of which were accumulated with sandbags, the two people who were lying on their stomachs shouted loudly.

Jiang Chen looked at the leaders next to him, such as Director Chen, Xu Shijie, Secretary Xu, Deputy Factory Director Zhang, and Director Ma, and saw that they nodded, so he shouted loudly: "Start testing!"

Of the two guns here, Ma Jun and Dongzi each took one and began to shoot: Boom, Boom, Boom、、、、、 Bullets began to shoot one shot at a time, this work may be relatively novel at first, but it became boring later, so that Dongzi complained, why not change to automatic and semi-automatic, what do you have to do semi-automatic, it is too slow to pull and hit once. Because it is a life test, the steel shell bullet used, this kind of bullet is relatively cheap, but it is also a 7.62mmX51mm bullet made according to the size of the copper shell bullet, so as to ensure the accuracy of the test, such a test finally completed the test with a gunshot after two days.

The overall performance of the two guns is not bad, a total of 2200 rounds were fired, the accurate type 1 was jammed three times during the test, and the precision type 2 was jammed twice during the test, which met the expected shooting standard, 2200 rounds is already a limit Now, the rifling of the two guns has been smoothed, and there is no point in fighting, the other parts perform well and can continue to be used, Jiang Chen analyzed the rifling smoothing or the problem of materials, but this Jiang Chen has no way to solve it now, but now this degree is also acceptable, if it is replaced with copper shell lead bullets, it should be able to reach 3,000 rounds, reaching a better standard。

The next is the accuracy test of firearms, mainly ballistics, this trial is a specially produced copper shell lead bullet, after a series of tests, the results are very good, which makes everyone very excited, from the factory leaders, down to the old workers, these people have been dealing with guns all their lives, I didn't expect Jiang Chen's firearms designed by this later life to be so good. During this period, there is an interesting thing that the latter part is tested by Jiang Chen, and a series of factors such as wind direction, temperature, humidity and so on should be considered in the test of 800 meters and 1,000 meters, which need to be calculated and designed with formulas, and Ma Jun and Dongzi are two big bosses, although they have been in school for a few years, it is still difficult to calculate this, and they can only be taught slowly in the future, so now only Jiang Chen can play in person.

The results of the test are that the best effective shooting accuracy of the Type 1 sniper rifle is 800 meters, and the best effective shooting accuracy of the Type 2 sniper rifle is 1000 meters. Not to mention the specific walking accuracy of the two guns, it is about 200m for 2cm, 500m for 5cm, 800m for 10cm, 1000m for 15cm, and the 2 type 1000m can reach 12cm.

Then there is a series of extreme environment tests, such as the hot shower test simulates the impact of the tropical humid climate on firearms, as well as the sand environment test, the bubble invasion test, and the extreme cold test, which is very difficult, Jiang Chen and they also deliberately moved a lot of large ice cubes from the warehouse of the cold drink factory and put them in a room, and put the gun in the room for 24 hours and shoot at the shooting hole, although it does not meet the standard of the rifle, but the overall result is still good.

The last item is to test the invasiveness of the bullet shot, after experiencing some gelatin soap plasticine (test three treasures, gelatin plasticine and soap!) test, the effect of the performance is still very ideal, the bullet is very stable in the air after the bullet is ejected, but once it touches the object, it will cause a short and rapid stall causing the bullet to roll in the body, causing great damage, which is the lethality. Finally, at the end of the preparation, someone proposed to test it with **, of course, this is also a test that is very close to actual combat, and Jiang Chen and the leaders agreed.

Looking around, I found two pigs raised by the old king in the canteen, these two are about to be slaughtered, and finally persuaded the old king who is full of tears, Dongzi and the fat man, two little devils who are like sweeping into the village, one by one, led by one and rushed over, and tied the pig with a rope to a place of more than 400 meters for testing, and the two pigs were separated by more than 50 meters, which was to reduce the fright of the other pig by shooting. Everything was ready to be completed, Dongzi and Ma Jun began to prepare to shoot, and some people who didn't know the truth next to them were watching this I had never heard of killing pigs like this, and Jiang Chen was hiding far away in the morning, he knew what kind of scene this was. Dongzi is a two-hundred-five, shoot first, bah! I saw that the head of a pig over there exploded, Dongzi jumped up happily, and the pig on the side was frightened and became irritable and began to pull the rope and run around.

I believe that many comrades are familiar with the name "headshot", everyone has heard of it, and it is like this, a bullet that shoots at the head of the human body at high speed must pass through the bones, that is, the skull. The skull was shattered into numerous fragments by a high-velocity bullet, just as a cannonball exploded to form countless fragments, and the fragments flew into the skull to form two kills. Because there is a large amount of soft tissue and cerebrospinal fluid in the skull, it is commonly said that there is also cerebral plasma. Then the bullet will also form a movement effect. Thirdly, there is pressure in the skull, and although the level of intracranial pressure is determined by the environment and individual conditions, there must be a pressure difference between the skull and the outside world. Once the bullet penetrates, the cranial pressure changes rapidly, and the fluid in the skull tissue flies out in a splatter. Creates the so-called headshot effect.

But this clean-up process is very painful, looking at Dongzi and Ma Jun's faces showing off their marksmanship, Jiang Chen is very funny, he thinks about it and says: "What are you happy about, hurry up and clean up the pigs, it's hot and deal with it quickly!"

Hearing this, several experienced old leaders, especially Deputy Factory Director Zhang, who had been a soldier, became unfriendly when he saw Jiang Chen's eyes, but he didn't object, just looked at Dongzi's happy appearance and smiled bitterly. Dongzi and Ma Jun went happily without paying attention to it, and the red oil tofu brain they ate this morning was conceivable.

Due to the presence of these two pigs and the test work these days, the food provided in the factory canteen is very good, braised pork, sauce and pork ribs, and the personnel involved in the test can eat in the canteen. Dongzi, Ma Jun and a few friends who helped saw the one who came up covered their mouths and ran out again.

Jiang Chen said while nibbling on the ribs: "This is the eleventh time, so you can't have a little luck!"

The people at the same table with him had black lines on their foreheads: "、、、、、、"

PS: A lot of people are talking about why I have a change a day, I really want to say, there are some cards recently, the code word is not very smooth, so I can only guarantee a change! But I will work hard, and strive for two changes as soon as possible! Looking forward to the three changes! I hope you will support! Are you satisfied with today's chapter? According to the standards of the two thousand parties, it is almost two changes, let's not make a mistake, just come once, everyone is satisfied, this can be regarded as a thank you for your support!