Why do hollow points cause more damage

Semi-wadcutters punch a larger hole in a target than hardball, and the hollowpoint allows for decent expansion. Frangible ammunition, designed to fragment upon impact, has also come to the fore in recent years. As defensive ammunition, frangible rounds are serviceable, as the fragments penetrate the target. However, frangibles are far less common and don't have the track record that JHP rounds do as defensive ammo.

There are a few hollow point designs that have eschewed jacketing, which can make them serviceable self-defense rounds. First, of course, is the lead semi-wadcutter hollow point. As mentioned, this was THE police round for much of the 20th century. Typically, these were grain loads in. The grain. In fact, this loading was common in service revolvers all the way into the s, as the last of the service revolvers were phased out of police use.

Monolithics are made of a single material. In the old days, these were just lead bullets. Today's monos are either solid hard-cast lead a popular handgun hunting bullet or a solid copper hollow point.

Solid copper hollow points or SCHP are made solely of copper. Since copper is less dense than lead, that means a lighter grain weight; 9mm copper rounds, for instance, tend to top out at grains such as CorBon's DPX load. Lighter grain weight and higher pressure, as you'd expect, confers extra velocity on SCHP rounds. As with other high-velocity ammunition, performance is predicated on design rather than mere speed; a high-velocity bullet of poor design still performs poorly. That said, selection of a quality load is critical for personal defense, so make sure you choose the right box and brand.

Not all ammunition is created equal, so not every hollow point bullet is going to work as well as another. Thus, it behooves a person to pick hollow point rounds that have a good track record of performance or - if too new to have one - have shown in multiple independent tests to do so. Speer and Hydra-Shok hollowpoints have both long been employed by police departments across the country. This has made them very popular carry ammo for civilians.

When it comes to hollow points, you need bullets that penetrate deep enough to create sufficient wounds but don't exit the target. You also need those bullets to expand reliably, and by an appreciable amount.

A 25 percent increase in diameter or more is good. Not every hollowpoint load does. Lead alloys and jacket design impact expansion greatly; some will expand more easily than others. As a result, you want to select carry ammo that doesn't overpenetrate and reliably expands. Overpenetration can lead to ricochets or even striking people behind the target, and insufficient penetration can mean insufficient wounding.

Reliable expansion creates larger wound channels but also ensures the round stays in the target, which is why police departments, hunters and concealed carriers use hollowpoints as defensive rounds.

Like reading this guide to hollowpoint ammunition? Is that right? Yes, I told her. You should use hollowpoints for self defense, assuming they are legal in your state as they are in mine. A traditional bullet used for target shooting typically features a round nose. Other bullet shapes designed for target shooting have blunt, squared-off noses. But whether the nose is rounded or flat, all target ammunition has one thing in common: a smooth, unbroken front surface.

Not so with hollowpoints! Hollowpoint bullets have a deep dimple in the nose, a hollowed-out area on the front surface.

When the hollowpoint bullet strikes a semi-solid object such as a human body , the dimple allows the bullet to expand, opening up almost like an umbrella or a parachute does.

Some hollowpoint bullets are also designed to fragment as they expand. As the hollowpoint bullet opens up, it makes a larger hole than a roundnose bullet of the same caliber would do. Hollowpoints that fragment produce extra wound channels to cause rapid blood loss. If it expands to 1. Some ammo will expand to nearly double its original diameter.

So why not design bullets that expand as much as possible? Because penetration and expansion work against each other. The more a bullet expands, the less it will penetrate due to friction.

This balance between expansion and penetration is a sophisticated act. What makes it even tougher is that bullets need to perform within design parameters even though they might have passed through a variety of barriers in front of the target like clothing, glass, wood, or automotive steel.

With so many potential variables, how to ammunition manufacturers optimize their designs? Enter the Federal Bureau of Investigation. The FBI ballistic laboratories have developed a rigorous and carefully designed ammunition testing protocol to help them objectively compare the performance of different calibers and ammunition types. When you consider the number of calibers, ammo companies, and unique loadings per manufacturer, it quickly becomes apparent that there are a nearly infinite number of variables.

The FBI test protocols give the agency a way to compare. While no lab test can accurately predict performance on the street, this test is generally considered the best overall approach and has been adopted industry-wide. Ammo companies design their offerings to excel in as many categories as possible in these FBI test scenarios. What varies is what is in front of those blocks. Barriers are put in place to simulate no clothing, heavy clothing, doors, walls, windows, and cars.

Ideally, a bullet will expand and penetrate properly after passing through any of these barriers. Most of the tests are performed from a distance of 10 feet, but a couple of the scenarios are replicated at 20 yards. The tests call for bullets to penetrate to a minimum of 12 inches and maximum of 18 and expansion is carefully measured. When you consider angles and the possibility of a bullet striking extremities first, the need for a bullet to travel 12 inches becomes clear.

In the Miami shootout of , agents delivered what would have been fatal hits to the armed subjects had their ammo penetrated deeply enough. Over-penetration is seen as a drawback too. Not only does the agency not want to see bullets pass through targets and risk hitting bystanders, over penetration implies wasted energy that could have aided additional expansion.

As a result, bullets that penetrate under 12 inches and over 18 are penalized in the scoring system. The wide range of scenarios quickly weeds out the poor performing ammunition from the more sophisticated loads.

Auto glass and steel can blunt the bullet and cause a similar result. There have been a number of ammunition solutions to this plugging problem over the years that went beyond designing a better hollow-point bullet.