I have seen a lot of answers, that are telling that it has more damage area and it fits in auto loaders better. I accept the second one, but not the first. Imagine a 9mm hits a vest and… nothing, probably a couple of broken bones, even though it has a larger damage area. Then the person takes their gun and shoots you. Your shots were probably useless. But if that 9mm was pointy it would, depending on the vest, penetrate it and hit the person, severely damaging the person. You’re now safe. That’s my scenario. So why are low caliber bullets not pointy?
In: Engineering
Pistol ammunition is limited in length by what can fit in the handle of the gun. So the bullets have typically higher diameters but are shorter than rifle ammunition.
Kinetic energy is mass * (velocity) ^2 To get high velocity you need large chamber pressure but that requires a thicker and stronger material. The result is most pistol calibers have heavier bullets than rifle calibers that have higher speeds. A ponty buller can require different shape feeding mechanisms to get it in the right position when loaded
If you make a 9mm bullet pointy is will be smaller and lighter and have less kinetic energy, there is a pressure limit in what guns are designed for
Pointy bullets often called spitzer bullets are designed to reduce air resistance and therefore range not to penetrate what they hit better.
Terminal ballistics is how a bullet behaves when it hits the target. You want the bullet to transfer all energy to the target, which means stopping. To do that a bullet needs to expand and deform. If it is hade and does not deform it likely passes through the target without transferring all energy that does less damage. Bullets are intentionally designed to expand to transfer more energy unless the are made for military usage where that is not allowed.
Bullets that stop on the target and do not pass through them have the advantage there is less risk of damaging someone behind them. This includes behind the wall. So for police and civilian usage low penetration is a good idea.
For armor penetration, the material is more important than the shape. Bullets typically have an outer thin copper layer and an internal lead filling, So it is quite soft. You want harder metal like steel to penetrate amour. You can put it inside the softer lead so you both have some part that deform to transfer more energy and to penetrate the armour
So bullet design is a compromise between what they do against a target with no armor versus a target with armor. The common 9mm Parabellum was designed in 1901 when body armor wasn’t a thing. The pressure you can have with metallurgy of the time was not as high as today.
There are more modern pistol calibers like FN 5.7×28mm that have a smaller bullet diameter that is pointed and travel at higher speed with similar kinetic energy. It is most known for its use in the FN P90 PWD but also the FN Five-seven pistol. Both weapons and the caliber were designed on a NATO request to replace 9mm parabellum for troops behind the frontline so they have weapons that could penetrate Soviet body armor used by paratroopers and other units that units behind the frontline could run into.
The trial of it and weapons based on HK 4.6×30mm was conducted in 2002 a lot of time after the required in large part because the Cold War ended. There has not been a need for weapons like in military units and the adoption like is was intended has been quite limited. The drawback of both is with armor-penetrating ammunition they do less damage on targets that do not have armor.
In practice, most of the time guns need to penetrate body armor rifles and carbines will be used. It is a simple solution then to adopt a pistol caliber that can do that. One of the main limitations of pistols is that the practical accuracy is a lot lower than rifles. The range is also quite limited.
Latest Answers