Hollow Point Bullets: Breaking Down the Details

You’ve heard of hollow point ammo; you’ve heard of full-metal jacket ammo. One gun chambered in 9mm Luger can fire either 9mm hollow point or full metal jacket rounds, right? 

Hollow point bullets (HP) have a depression in the nose of the bullet. The reason for this is that when the bullet contacts a soft target, the bullet expands (this is called disruption in ballistic terms) creating a wide wound channel. It also causes cavitation, an area of low pressure behind the bullet that results in rapid expansion, resulting in extreme tissue trauma.

Hollow point ammo is designed to hit a target, create a wide wound channel, dump all of its energy effectively, and stop before penetrating beyond the target. It is also usually loaded to fairly high chamber pressures to generate more stopping power. Often, hollow point bullets are heavier than their FMJ counterparts, though this is not always the case.  

As for full metal jacket ammo (FMJ, sometimes referred to as ball ammo), these bullets consist of a lead core that has a copper jacket drawn down from the nose, completely enclosing the bullet except at the base. They are designed for reliability, ballistic stability, accuracy, and penetration. All else being equal, an FMJ bullet will penetrate much farther through a target than a hollow point bullet. 

This means that FMJ rounds are inferior when it comes to stopping most threats. They also produce a risk of overpenetration, which can put unintended targets behind the intended target at risk. 

With that said, the accuracy, reliability, and comparative low-cost of FMJ ammo make it popular for drilling and range training, whereas hollow point bullets remain the standard and the preferred choice when the objective is to rapidly neutralize a threat.

In the realm of hollow point bullets, there are both bonded and non-bonded hollow points. In a bonded hollow point, the lead core of the bullet is either chemically or physically bonded to the jacket; some manufacturers melt the lead till it adheres to the copper (physically) or they use an electrochemical process that fuses the jacket and core together.

Bonded hollow point bullets tend to expand in a very controlled, metered, reliable fashion, and since the core and jacket are inseparable, they cannot come apart and so these bullets rarely overpenetrate. The process of bonding gives bullet manufacturers great control over precisely what happens when a bullet contacts a target.

With a non-bonded bullet, the core and jacket are not bonded, and can separate freely on impact. This often results in explosive expansion, although it can be unreliable. Moreover, non-bonded bullets can be less reliable on contact with glass and other hard materials. This makes shot placement critical - although in truth, it always is.

Another consideration with non-bonded hollow point bullets is that they are far more cost-effective to manufacture and therefore are more affordable than bonded bullets.

A hollow point bullet’s jacket may be either skived or unskived. Basically, skiving the jacket refers to the process of creating deep striations that run from the nose of the bullet, longitudinally down to the base.

These serve as weak points in the jacket where the jacket will tear back and away, resulting in consistent, reliable expansion and creating a predictably devastating wound channel.

There are high quality hollow point bullets that are skived, and others that are unskived. While a skived jacket does increase the reliability and consistency of expansion, it is not the case that a jacket must be skived in order to produce reliable results.

Here are some other considerations to take into account with hollow point ammo:

Hollow point ammo can be ineffective (or rather, lose some of its efficacy) when there is an interposing barrier between the intended target and it. For instance, some lose their efficacy when passing through glass. Others are not as reliable on contact with a target that is wearing heavy clothing. In some instances, clothing can “plug” the nose of the hollow point, causing it to react almost like a jacketed bullet. Some lines of ammo, like Federal HST, have been tested extensively to perform effectively even through several layers of fabric. Hollow point ammo is not as reliable in some firearms as in others, since the sharp “edge” of the nose can hang up on chamber edges and feed ramps.

FMJ is considerably more cost-effective than hollow point ammo and should be used in lieu of hollow point for the purposes of training.

At the same time, FMJ ammo is more likely to exit the target, creating a higher risk for bystanders. Additionally, FMJ ammo is more likely to produce a risk of ricochet than hollow point ammo.

What Are Some of the Best Lines of 9mm Hollow Point Ammo?

There are many brands that are known as high-quality hollow point ammo, and some of the following lines are well-respected in the industry for their reliability and stopping power:

• Speer Gold Dot and Gold Dot G2
• Federal HST
• Federal Hydra Shok
• Remington Golden Saber
  
  These are just a few of the lines we carry, though there are other excellent lines of hollow point ammo; you can learn more at the previous link or get in touch with our representatives for more information.