Shrapnel is nothing new, even in the era of front-loading smoothbore guns, it was widely used in various countries, and it was often used in the early days of the Imperial Army, when smoothbore guns were still used.

However, the howitzer shrapnel technology at that time was unstable, so although it can often be seen in actual combat, most of the time the artillery units prefer to use solid bullets at medium and long distances in long-barreled field guns, especially the use of small angle design, so that the solid bullets bounce after landing for the first time, forming multiple jumps with low height, and the killing effect is quite good.

Howitzers are used on short-barreled howitzers or mortars to kill people or horses, but the spherical grenades of the pre-loading smoothbore gun era are not too lethal because of the limited charge and the strength of the shell shell, and they are basically useless for solid bunkers.

As for shrapnels, they are used even less, only on some special occasions, they are used, and the failure rate is very high, and there are often early or delayed explosions, and even duds.

When the Imperial Army began to equip rear-loading rifled guns, with the maturity of collision fuze technology, the larger volume space brought by the cylindrical projectile body, coupled with the particularity of the rifled gun, made the main bullet re-transformed into a new cylindrical high-explosive grenade.

However, it also uses a special shrapnel for breech-loading rifled guns, but it is still not too easy to use.

The main problem is the fuse, how to make the shell explode on time on the head of the enemy, which is a difficult problem.

With the passage of time, the technology has slowly improved, and after gradual improvement, the shrapnel technology used now has gradually improved, and after the shrapnel is shot, most of them can also explode on time above the head of the intended target.

With the direct fire support of the division's 75-mm howitzers, the attacking enemy troops suffered continuous casualties even when they were lying on the ground, and finally they could not help but retreat.

But after this first attack retreated, the enemy was obviously unwilling, and soon organized a second and even a third attack, and during the third attack, they even organized nearly 4,000 troops to attack the small land of Jialiu!

But without exception, they were all repulsed by the 15th Regiment.

Wen Zuoxin was not surprised by the defeat of the enemy!

His 15th Regiment, supported by hundreds of barreled artillery, dozens of rapid-fire mortars, and nearly 20 heavy machine guns, still paid nearly 200 casualties in order to seize the No. 6 Heights!

Now that a whole regiment is here, it has its own intensive firepower of rapid-fire mortars and heavy machine guns, and a full battalion of divisional artillery in the rear to provide direct fire support.

If the other party can still rush up, then he Wen Zuoxin will have to directly pull out his knife and kill himself!

And this defensive operation also made Wen Zuoxin deeply feel the powerful role of the heavy machine gun!

In offensive operations, the role of heavy machine guns is not very obvious, even if it can provide fire suppression, but it is still not very obvious, and the real takedown of the No. 6 heights is more dependent on the intensive curved fire of rapid-fire mortar guns and the artillery support in the rear.

And then there's the decisive charge of the infantry!

But in defensive operations, the role of artillery and even rapid-fire mortars is naturally still strong!

But the role of a heavy machine gun is no less powerful!

When the enemy braved his own artillery and rushed to a distance of several hundred meters, especially about 500 meters, his heavy machine guns began to strafe the enemy, and the density of fire formed was amazing, and the attacking enemy troops were easily caught in the crossfire formed by multiple heavy machine guns.

So much so that many of the enemy's soldiers fell not under shells, but under machine-gun bullets.

Three attacks by the enemy did not even manage to break through to three hundred meters in front of the infantry positions of the 15th regiment.

In other words, the vast majority of them were killed or wounded or retreated without even firing a shot.

Although the effective firing range of this rear-loading rifle is several hundred meters at every turn, and the aiming scale of the Luoan III rifle can reach 1,000 meters, when the military originally engaged in this kilometer scale, it was calculated based on surface killing.

Because at the beginning, when the Imperial Army was equipped with rear-loading rifles, the enemy was still playing line operations, and when facing the enemy, there was no need for any accurate shooting, just just aim and shoot at the enemy line, so sometimes, against the enemy troops in line formation, the troops of the Imperial Army even dared to shoot at five or six hundred meters!

But soon this situation will not work, and the enemy will also begin to learn to be smart, stop playing queues, and change to skirmishers.

And as the enemy army was generally equipped with breech-loading rifled rifles, they also began to imitate the light infantry tactics of the Imperial Army, which was fought in hiding.

If you want to hit the enemy, you often need to aim at a single target accurately, which requires the accuracy of the rifle and the marksmanship of the soldier!

However, due to the soldier's visual ability, even a soldier with good marksmanship can only shoot accurately at a distance of about 300 meters.

Therefore, if both sides are hiding and shooting at each other, in fact, the combat distance is generally within 300 meters, and beyond this distance, for the vast majority of ordinary soldiers, they will not be able to hit those enemy soldiers who are hiding their heads and tails.

And the enemy did not even rush to a distance of 300 meters, which also means that they have not even entered the regular infantry engagement distance.

However, before that, they had already been killed by the heavy machine-gun fire and rapid-fire mortar fire of the 15th Regiment of the Imperial Army.

This made them very uncomfortable!

The enemy retreated, which also gave the 15th Regiment a rare time to rest and replenish after a full day of fierce fighting.

Towards evening, the Fourth Division, including the 15th Regiment, and other attacking units had basically stopped their large-scale attacks.

With the situation that the sky is about to get dark, it is too difficult to continue a large-scale attack, and accidents are prone to occur.

Moreover, the offensive on the first day was relatively smooth, and breakthroughs were made in many positions, especially the capture of Heights No. 6, which allowed the attacking troops to obtain a solid and prominent artillery position.

The artillery unit was so bold that it directly deployed a heavy artillery battalion with 150-mm howitzers and 100-mm field guns.

This artillery position can cover the entire battlefield in Zhenbei City!

This will bring great convenience to subsequent offensive operations.

At this time, Liang Chenglei and his men needed to study the next day's operation, and at the same time, they also used this night to strengthen their positions and replenish some troops with relatively large losses and ammunition and weapons.

Among them, the 15th Regiment, which has always been on the front line and fighting on the most difficult front, has obtained valuable soldiers and material replenishment.