November 24, 2021
The .45 Auto, also known as the .45 ACP (ACP is an acronym for Automatic Colt Pistol), is likely one of the most famous American handgun cartridges of all time. It was designed by John Moses Browning in 1904 for what was an experimental semi-automatic handgun. This evolved and ultimately was adopted as the U.S. Pistol Model 1911 and its cartridge as the U.S. .45 Caliber. The U.S. M1911 in .45 Auto is one of the longest-serving handguns of the U.S. Military, with it issued from 1911 until its replacement in 1985 by the Beretta M9 9mm service pistol. Even with this "replacement", many U.S. Special Operations Forces still used and issued the M1911 .45 caliber handgun. Recently the U.S. Marine Corps re-adopted the Colt 1911 CQBP, which is an updated 1911 for the 21st-century battlefield.
The .45 Auto cartridge is a rimless straight-wall case topped with a .451-inch projectile. Projectile weight typically ranges between 185 to 230-grains. Velocity range typically falls between 830 to 1,000 feet per second. What sets the .45 Auto apart from other handgun cartridges is its long-standing reputation as a "man stopper". Enter any gun shop, gun forum, gun webpage and someone will likely be talking about the "stopping power" of the "Lords Caliber", their beloved .45 Auto. So, where and how exactly did the .45 caliber initially get its reputation as a "man stopper"? During the Moro Rebellion of the Philippine-American war, it was found that the Moro tribesmen would use mind-altering drugs and wrap themselves in makeshift body armor (from tree resins and cloth). During a frontal charge on American soldiers, Moro tribesmen could take a full cylinder of the anemic .38 caliber Long Colt from the issued service revolver, showing little to no initial effect, and continue to advance.
Due to this, the previous standard Colt Model 1873 in .45 Colt would be reissued to some American troops. The larger .45 Colt cartridge is said to have provided superior results over the .38 Long Colt, putting the Moros down much faster and more effectively. With this information, along with the results from the Thompson-Lagarde tests of 1904, it was decided by the U.S. Army Ordnance Corps. the next official service pistol of the U.S. Military would be a .45 caliber. This, coupled with the .45 ACPs success from side arms, and then submachine guns, during the World Wars would give it a legendary, near mythic status among hand gunners and firearm enthusiasts.
So, how does this history translate to a more modern self-defense use, especially considering the advancement of projectile technology across the board? Is it still the "man stopper" it is portrayed to be, with the "most stopping power"? The answer is a bit complicated and easiest to say both yes and no. For starters, handguns in duty calibers are typically a much less desirable weapon for defensive use (over long guns such as rifles and shotguns). Their lower velocity makes them reliant on penetration to vital organs or damage of vital areas of the body. Studies of police shootings involving handguns and long guns shows more than one handgun projectile is likely required to stop a determined attacker. Basically rifles and shotguns offer greater terminal performance over service pistols. This isn't to say a handgun is a "bad choice" for defensive use. It offers the user concealment, maneuverability and typically good capacity. That said, duty caliber handguns simply offer mediocre terminal performance overall compared to long guns, and the .45 Auto is no exception.
The .45 Auto suffers from many of the same limitations and downfalls as the .380 Auto and .38 Special cartridges, chiefly its low velocity. The average 230-grain .45 Auto load will rarely break 900 feet per second, with typical velocities falling between the 825-890 feet per second mark. Keep in mind this is from a 5-inch barrel. These factory 5-inch velocity figures are due to the 1911, with its 5-inch barrel, being the most common handgun found in .45 Auto. Typical barrel lengths on “duty” or “Concealed Carry” handguns fall from 4 to 4.5 inches, meaning the already low velocity of the .45 Auto is further reduced, typically falling 5-10% from advertised muzzle velocities.
With these already low velocities, the threshold in which a typical .45 Auto hollow point will reliably expand is relatively limited. So, the .45 Auto needs to retain as much velocity as possible to consistently perform well, especially through heavy clothing and other light barriers. Even premium offerings, from trusted brands will suffer from this issue. Take the Barnes TAC-XPD, solid copper hollow point offering. This uses the 185-grain, XPD projectile, famously used by premium ammunition manufacturers such as Black Hills, early Cor-Bon and Barnes branded ammunition itself. Advertised at 1,000 feet per second, the actual chronograph results show an 11.85% decrease in velocity, with an average that didn't even break the 900 feet per second mark, coming in at 894 feet per second from my Heckler and Koch USP V1.
As with other low velocity handgun options, certain ammunition companies try to improve the consistency in terminal performance, and promote expansion, by increasing velocities well past that of standard loads. Many + P (Plus Pressure) offerings and boutique offerings from companies like Buffalo Bore, Underwood, Double Tap and Cor-Bon offer exceptional expansion and impressive wound cavities. However, these loads often come with the tradeoff of substantially higher, and sometimes severe, recoil.
Having experience with Cor-Bon's near outrageous 165-grain offering and their equally impressive 1,250 feet per second numbers, offerings such as this are a completely different animal than that of a standard .45 Auto Defensive load. Recoil is sudden, abrupt, severe and much like that of a .357 Magnum loaded with 125-grain JHPs. To say recoil mitigation is poor is an understatement, and this is from a Government model 1911 and Smith and Wesson 4506, both are large frame and heavy firearms. Fast follow-up shots come slower with loads such as this. While the numbers are knocking on the door of .45 Super, all in a standard .45 Auto handgun, the heavy recoil, slower follow-up shots and more difficulty to train with make this a knock on a door I personally will not answer.
Projectile choice is paramount when choosing a .45 Auto, in terms of reliable terminal performance, especially from duty length barrels and shorter. Safe bets for solid performers include: Federal's famed HST 230-grain standard pressure and +P offerings. Both of these not only meet, but exceed FBI protocol and barrier testing. They also perform consistently through varying barrel lengths, including those ranging into the high 3 inch lengths. Another is the age old CCI/Speer favorite, the Gold Dot 230-grain standard pressure. I find the +P variant a bit much in the recoil department, especially from non-steel and alloy framed handguns (as I use FN's FNX Tactical and Heckler and Koch's USP for the majority of my testing). While I do respect the performance offered by Sig Sauer's V-Crown in 9mm, the .45 Auto failed to perform in heavy clothing barriers, as did: Winchesters PDX-1, Ranger T-Series, Winchester Silvertip 185-grain, Federal's Hydra-Shok 230-grain, Federal's Hi-Shok 230-grain, PMC/El Dorado Starfire 230-Grain and PMC Bronze 185-grain JHP. One offering that produced impressive numbers, also exceeding minimum penetration depths from the FBI is Federal's 185-grain Hi-Shok JHP. It produced impressive expansion, a great permanent wound path and penetration; but the projectile had substantial jacket separation and lost almost 30% of its projectile weight.
So, has the .45 Auto been overshadowed by modern projectile technology and performance from smaller calibers? In some ways, yes and in others, no. For military use, or states which do not allow its citizens to fully exercise their Constitutional rights (restricting them from using expanding projectiles such as JHPs), the effectiveness of the FMJ 230-grain .45 over smaller calibers is not only noted, but historically recorded. It is also true that the ".45 doesn't shrink" (an argument used by those who refuse to acknowledge smaller caliber handguns). However, it is also scientifically factual that a .45 caliber JHP runs a large chance that it will not "grow" (expand) either, unlike faster but smaller calibers, such as the 9mm and .40 S&W (due to their velocity advantage and wider velocity buffer, allowing the projectile to perform as designed). In the end, many ammunition companies design their ammunition to perform around criteria set by the FBI, and that performance is set from the most likely barrel length the populace will use. With the .45 it is from a 5-inch barrel.
Whatever you choose for caliber, I recommend researching credible sources for ammunition terminal performance. Then train hard and train often, because in the end shot placement, recoil mitigation, capacity and ability (a marriage between equipment and person) is the ultimate threat stopper, not caliber.
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About the Author:
Michelle Hamilton has a Bachelor’s degree in Criminal Justice/Homeland Security, is a serious student of wound ballistics, military history, small arms design and manufacturing and is a competitive shooter.