When it comes to selecting a handgun for carrying in the great outdoors, the vast number of possible configurations and calibers to consider can be overwhelming. One cartridge that’s frequently mentioned by those interested in self-defense and handgun hunting alike is the 45 ACP. Many gun owners boast about its sheer bulk and “stopping power,” but is that true? Is the 45 ACP a good idea for defensive purposes, whether you need it against two-legged or four-legged attackers? Does it work for handgun hunting? Read on to find out.
What is the 45 ACP, Really?
The 45 ACP was designed by John Moses Browning in 1904. It was created in response to the U.S. Cavalry’s desire for a more capable defensive round after the military realized that their existing 38 caliber was less than ideal That situation took place during the Moro Rebellion during the Phillipian/American War in the early 1900’s, a battle where the Moro juramentado proved they could take bullets from 38 Colts and keep on going. Granted, the juramentados were known for drugging themselves into feeling no pain, but they were also incredibly zealous fighters. This led to the infamous Thompson-LaGarde Tests of 1904, whose results reported a 45-caliber bullet was necessary to stop threats during battle.
Because the 45 ACP was clearly created for combat, a lot of gun owners feel that means it’s still “The Best Thing Ever.” However, ballistics have come quite a way since the early 1900s.
| Cartridge | 9x19mm Parabellum | 45 ACP | 10mm Auto |
| Designer | Georg Luger | John Moses Browning | Jeff Cooper/FFV Norma |
| Designed In | 1901 | 1904 | 1983 |
| Country of Origin | Austria | United States | United States |
| Produced | 1902-Present | 1905-Present | 1983-Present |
| Case Type | Rimless, Tapered | Rimless, Straight | Rimless, Straight |
| Bullet Diameter | 0.355 inches | 0.425 inches | 0.400 inches |
| Neck Diameter | 0.380 inches | 0.473 inches | 0.423 inches |
| Rim Diameter | 0.392 inches | 0.480 inches | 0.425 inches |
| Case Length | 0.754 inches | 0.898 inches | 0.992 inches |
| Overall Length | 1.169 inches | 1.275 inches | 1.260 inches |
| Maximum Pressure | 35,000 psi (SAAMI) | 21,000 psi (SAAMI) | 37,500 psi (SAAMI) |
Does Size Matter?
For the purposes of a size comparison, check out the graph below to see how the 45 ACP stacks up alongside the 9mm and 10mm.
It’s common to think that a bigger bullet must be better because it makes a larger hole. Unfortunately, that’s an over-simplification that ignores how ballistics work. So, although the 45 ACP has a larger-diameter bullet, that doesn’t necessarily mean it’s the most effective option.
For example, take a look at the maximum loading pressure of each cartridge listed above, as noted by the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI). The 45 ACP has a far lower maximum pressure than either the 9mm or 10mm. That translates to less propellant to move that bullet toward the target.
45 ACP Ballistics
From a ballistics perspective, the 45 ACP does have the ability to produce more energy than the 9mm—but not more than the 10mm—and it is outdone for velocity by both the 9mm and the 10mm. However, when comparing 45 ACP to other cartridges, it’s the sheer grain weight of the bullet many people point to as why it seems to be the clear winner.
Yes, the 45 ACP generally has a heavier bullet than the 9mm or 10mm, but that bullet is being pushed downrange at slower speeds. In addition, the 45 ACP bullet loses energy along with velocity, so it might have a larger diameter bullet, but the end results don’t speak to that being a good thing. The 9mm is lighter in weight, but it moves fast. The 10mm is slightly lighter but moves quickly and produces fantastic energy.
Pros and Cons of 45 ACP
The pros of using the 45 ACP for defensive and/or hunting purposes are usually listed as follows:
- Bigger, heavier bullet
- More than a century of proven use
- Use in wartime
- “Softer” shooting, when compared to 10mm Auto or Magnum cartridges
From a realistic perspective, these are the cons of using 45 ACP:
- Bullet weight translates to less velocity and faster drop rate
- It produces fairly significant recoil without providing the benefits to go with it
- Rapid fire can be unmanageable for many shooters
- It loses benefits of energy transfer rapidly with distance
- Its lower maximum pressure means lower velocity
- It has less capacity in the majority of guns chambered in 45 ACP compared to 9mm and 10mm
- It is not a consistently effective, ethical choice for handgun hunting
Bottom Line: Good for Defensive Use?
My opinion is that, no, the 45 ACP is not ideal for defensive purposes or handgun hunting. That does not entirely negate its value, because it certainly can work given the right set of circumstances. Keep in mind that issues like overall capacity and distance come into play in real-life self-defense scenarios, so you’re going to want the option of more rounds of ammunition and good ballistics when you’re fighting for your life.
This means that from a defensive perspective against two-legged threats, the 9mm has surpassed 45 ACP. Technology has made a number of advances possible, and those make the a 9mm a great self- defense cartridge.
As for handgun hunting or defense against four- legged threats, 45 ACP is outshined by cartridges such as a 10mm. In fact, there are countless stories of game and predators wounded and lost when shot with 45 ACP. That doesn’t mean 45 ACP is a terrible idea and can never be used, but it should give you pause when considering hunting with it. After all, it’s your responsibility as a hunter to make an ethical, clean shot. The 45 ACP reduces the odds your hunt will be good from an ethical standpoint.
If the only gun available to you for defensive use is one chambered in 45 ACP, make sure it’s loaded with the best possible ammunition. You should also be sure to train. Consider saving up for a different handgun for carry, too. Simply being capable in the right circumstances doesn’t make a gun the ideal choice. Because when it comes right down to it, ballistics say 45 ACP is no longer king of the ammunition hill, whether you like it or not.
