Caliber & Types of Bullets

You've probably heard someone use the term “knock-down” or “stopping power” associated with a bullet's perceived ability to stop a threat. Unfortunately, there is no way to measure “knock-down/stopping power” because it is a “digital” concept with a multitude of variables. So the term becomes meaningless. However, we can measure the amount of energy transferred to a target AND we can see the type of wound channel a specific bullet is likely to produce in a ballistic gelatin (simulating a human body)… with no hard impediments that could deflect a bullet - such as bones.

Following the aftermath of the 1986 “FBI Miami shootout”, the FBI “ Handgun Wounding Factors and Effectiveness” paper stated: “Penetration less than 12 inches is too little, and, in the words of two of the participants in the 1987 Wound Ballistics Workshop, “too little penetration will get you killed”. Given desirable and reliable penetration, the only way to increase bullet effectiveness is to increase the severity of the wound by increasing the size of hole made by the bullet. Any bullet which will not penetrate through vital organs from less than optimal angles is not acceptable. Of those that will penetrate, the edge is always with the bigger bullet.”

As we see in the chart to the right, all of the rounds tested exceeded 12“ penetration. And while a wound channel in ballistic gelatin may not tell the entire story, it does give us ideas as to what a specific bullet does. Ultimately, shot placement is the most important factor… and those who choose a smaller handgun have already made that compromise in accuracy.

<note>Most of the FBI agents involved in the 1986 “FBI Miami shootout” were armed with either .357 Magnum revolvers or .38 Special +P revolvers - which proved slow and difficult to re-load. The two agents who were killed were carrying Smith & Wesson Model 459, 9mm semi-automatic pistols. Although the suspects had been shot numerous times, they continued to fight on. One suspect was shot 12 times, and the other was shot 7 times before the fight ended.</note>

More Studies
Greg Ellifritz performed an extensive study involving over 1,700 real world shootings - in an effort to statistically determine which caliber bullet had the most / best “stopping power” (defined as immediate incapacitation).

You can read his results at: An Alternate Look at Handgun Stopping Power

Or, you can watch a fantastic video summarizing his results:

<note important>Spoiler Alert: Greg Ellifritz's study showed that every caliber above .32 caliber was effective. Surprisingly, the degree of effectiveness between the .380 caliber and .44 Magnum is statistically insignificant PROVIDED that the bullet hit the attacker in either the head or torso. Ultimately, as already stated… shot placement is key.

If you can't hit your target, it doesn't matter what caliber your handgun is. Again, ensure that you can handle the recoil of the handgun and caliber you choose. </note>

When purchasing ammunition, you will be presented a dizzying array of different types of bullets. For example…

Ball Bullets The most common bullet for practice has a rounded nose and is typically called a “ball” type bullet (shown above as “Full Metal Jacket”). These bullets can be made of solid lead, or have a lead or zinc core surrounded by a “Full Metal Jacket” (FMJ).

Hollow-Point A hollowpoint bullet is designed to expand upon impact.This flattens the bullet to that it either stays within the body of an attacker OR leaves a very large exit wound.

You may have heard (or read) that the 9mm cartridge has greatly improved over the past several years. In itself, that is a false statement. What has greatly improved are the 9mm hollow-point bullets (aka “Personal Defense” ammunition).

Some of these designs are intended to both flatten and flare - creating sharp jagged edges that, as the bullet is spinning when it enters a body, will cut and tear tissue to increase trauma and blood loss… in an effort to more quickly incapacitate an attacker.

The above photo is of Premium HST 9mm, .40 S&W and .45 ACP cartridges along with their fully expanded bullets.

Some pistols will handle many types of bullets while others will not. For example, the feed ramp in a 1911 pistol was designed to feed 230 grain (weight of the bullet/projectile) FMJ (Full Metal Jacket) bullets with a rounded nose into the barrel. And while some people like the idea of loading their 1911 with hollow point bullets, most hollow point bullets are designed with “angled/slanted” sides and a flat nose. In order for the 1911 feed ramp to properly load a hollow point bullet, it MUST have rounded sides. In fact, the factory Sig Sauer P-220 magazines are designed to prevent a .45 ACP magazine from loading the incorrect cartridges. This is a GREAT idea to help keep users from loading a cartridge that the pistol is not designed to feed.

Also, there are cartridge casings made of brass or steel. The main difference is that the brass casings will expand when fired - preventing much of the GSR (Gun Smoke Residue) from traveling back into the firing mechanisms of the pistol. The steel casings are harder than the soft brass casings, so they will not expand nearly as much as the brass casings. Consequently, using steel cased cartridges tends to create a “dirtier” gun (requiring more frequency and greater “attention to detail” when cleaning).

So before you buy any “special” ammunition, check with a SME for your specific pistol in advance. For example, USMC Veteran Matt Stamp has a GREAT video on ammunition for the 1911 at: ”1911 Tips, Ammo“. Where people insist upon using hollow point .45 ACP ammunition, he only recommends Federal Personal Defense HST 45 Auto, Federal Personal Defense HST 45 Auto +P, and Winchester USA .45 ACP 230 Grain Jacketed Hollow Point.

<note warning>The 1911 was designed to fire “ball” ammunition. Consequently, it tends to have difficulty chambering bullets with flat noses (e.g., many hollow point bullets, wadcutters). While Winchester does manufacture a hollow point bullet designed specifically for the 1911 (the WIN 1911), there are few hollow points that will reliably chamber into a 1911. So if you want a pistol that fires .45 ACP bullets with these other configurations - and don't mind compromising on the straight slide trigger - consider the HK45 Tactical, Glock 21, Glock 30, Glock 36 , Glock 41 and/or Sig Sauer P220 Legion.</note>