This has to be the most heavily debated topic of any given gun related forum. Starting as "9mm vs. .45" during WW2, with many new caliber choices the caliber wars continue to rage. Some believe in big bullets, some believe in lighter, faster bullets with higher simple energy numbers, some believe in shot placement; all are equally mistaken. The potential effectiveness of any bullet in a defensive shooting is always an issue of probabilities that factor in caliber, weight, velocity (resulting in penetration and expansion), shot placement, and even the physical condition (drugs, rage, size, etc.) of the threat you are attempting to neutralize. You will hear of threats dropping immediately from a .25 ACP and you will hear of threats that continued to fight despite a solid .44 Magnum hit but these are rare exceptions and should never be considered representative in any way of overall stopping power potential
. They are nothing beyond extremely rare incidents that have minimal impact on the overall averages used to calculate overall stopping power potential
. While I dismiss the theory of "stopping power", I fully embrace the concept of stopping power potential
Before proceeding further I must differentiate between two completely separate issues, shooter performance and bullet performance. The recommendations I make throughout this guide assume that you are capable of proper shot placement (shooter performance) and other defensive tactics. If you remove the human element (your ability to shoot) and limit your comparison to bullet performance its hard to argue with "bigger is better". Despite lower simple energy numbers, bigger and particularly heavier bullets carry more stopping power potential
and this is clearly substantiated in history.
Around the turn of the century (1900) the US Army replaced the M1873 peacemaker .45 Long Colt revolver with a much lighter and faster .38 Long Colt (in a double action revolver). In 1902 during the American-Philippine war the US Army was sent into battle in the Philippines against the Moros Tribesmen where for the first time they faced enemy soldiers on heavy opiate based drugs of that era. US soldiers emptied their .38 Long Colts into the advancing tribesmen who continued to advance most often spearing and even beheading the US soldier before falling dead from their gunshot wounds. It quickly became obvious that the lighter .38 Long Colt was not up to the job of stopping the Moros Tribesmen. The Army replaced the newly issued .38 Long Colts with the recently retired M1873 Peacemaker .45 Long Colt and put them back in service.
Just as it had in the previous century, the .45 Long Colt proved itself by dropping the Moros Tribesmen most often with a single shot (yes, a single torso hit from the .45 Long Colt proved superior to 5 and 6 shots from the .38 Long Colt!). This is documented US history and there is no disputing it. The .45 Long Colt played a crucial role in winning the war, and this directly lead to the development of the .45 Automatic Colt Pistol (.45 ACP) which served our troops equally well through two world and many smaller wars.
In and of itself with all else being equal (shot placement, etc.) hitting a threat with a 230 grain .45 caliber slug is not the same thing as hitting that same threat in the same place with a 115 grain .355" slug despite its considerably higher velocity. With typical handgun velocities at typical defensive handgun ranges bigger simply is
better, but how much better is the question, and at what cost? 20 years ago there was a significant difference in ballistic performance of the 9mm compared to the .45 but modern ballistic science has brought the 9mm closer to the .45 than ever before. While I still believe bigger is better (you don't shoot elephants with small and fast bullets, you shoot elephants with big, heavy bullets), it's hard to argue with a 147 grain 9mm bullet that penetrates nearly 14" and has been shown to expand to .72" (147 grain federal HST).
Although true and accurate, does the example of the Moros Tribesmen mean that everyone should carry the .45? Absolutely not
. Although the .45 would serve any
one very well just as it has throughout history, this does not make it the superior choice for every
one. .45 caliber weapons are either relatively large or they have very limited capacity and this limiting factor rules out the .45 for many. To confuse the issue even more, although I firmly believe that when all things are equal bigger is better, all things are rarely equal when you factor in the human element. Although the 180 grain .40 offers slightly more stopping power potential than a 147 grain 9mm, that does not necessarily make it a better choice for carry due to many reasons. If you find the .40 recoil uncomfortable you probably won't be able to hit with it with as much confidence as you would with the 9mm. Capacity is another issue, especially when you factor in cover fire. Is it better to have 8 rounds of .45 in your weapon or 16 rounds of 9mm? The answer to this question will be as unique as the individual in question.