ACP is a typical term you"ve most likely seen top top ammo and firearms. Yet what does the mean and what space the term"s roots?

Newcomers to the human being of guns and also ammo generally have tons of questions. Even those of united state who thrived up in the culture can be perplexed by every the total lingo and also alphabet soup acronyms. One of those typical questions is, “What go ACP stand for?”

Although us may frequently see those three letters, no everyone knows specifically what castle mean.

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What walk ACP was standing For?

The quick answer? ACP means “Automatic Colt Pistol.”

The much longer answer? The letter “ACP” are supplied to denote various cartridges design by john Browning because that Colt semi-automatic pistols. These straight-sided cartridges space all similar in appearance and include .25 ACP, .32 ACP, .38 ACP, .380 ACP, and .45 ACP.  However, if we protect against right there, we miss out ~ above a an extremely interesting story.

The remarkable John Moses Browning

In the civilization of firearms, there might be no figure much more legendary 보다 John Moses Browning. Born in Utah in 1855, Browning built his an initial firearm at the tender period of 13 using tools and also materials from his father’s gun shop.

At 24, Browning patented a self-cocking single-shot rifle through a fallout’s block action. He later sold the style to the Winchester Repeating arms Company.

In 1889, man Browning was shooting v some friends once he made an monitoring that would certainly ultimately adjust the course of guns history. As the guys took transforms shooting, Browning i found it that some tall grass would certainly bend once his quick friend, will certainly Wright, fired his weapon. Each time will certainly shot, the muzzle blast from his gun would certainly send the weeds rippling, denote a release of energy. This offered Browning the idea come harness the wasted power to occupational the firearm’s action, cycle the next round into the chamber. By the finish of that exact same day, Browning had arisen a prototype because that his own self-loading pistol. 

Changing the world of Firearms

In January 1890, Browning filed a patent because that a gas-operated device gun, a architecture inspired by that very first self-loading prototype. End the following several decades, Browning filed over a dozen an ext patents for both gas and also recoil activate self-loading weapons. 

In 1895, Colt Manufacturing agency began production of the an equipment gun Browning had designed. This to be the beginning of a lengthy collaboration in between Colt Firearms and also John Browning.  although Browning no the very first person to architecture a semi-automatic pistol, he to be the an initial to develop a slide enclosing the barrel and also the firing mechanism. Created by both Colt and also the Belgian firearm company, Fabrique nationwide de Belgique (FN), Browning’s self-loading pistols range from the minuscule .25 caliber to the an ext substantial .45.

John Browning was a genius when it concerned firearms design and also innovation. In fact, this male invented more firearms than any type of other gunmaker in the background of the world. We have him to give thanks to for the Winchester version 1894 lever-action rifle, the Remington design 1905 semi-automatic shotgun, the M2 Browning heavy maker gun (which still serves as the conventional heavy device gun the the United states military)… and the legendary Colt version 1911 semi-automatic pistol. 

The Colt 1911

When most human being hear automatically Colt Pistol, the first thing that pertains to mind is the Colt .45 ACP design 1911.  For much more than a century, man Browning’s semi-auto M1911 has actually traveled with US troops come battlefields and also military hot spots about the globe.

The weapon (and the .45 ACP ammunition designed to go through it) was designed in an answer to America’s an initial overseas insurgency, the Philippine-American War.  unless you to be paying close fist in high school history class, you most likely don’t remember much around this conflict.

Although overshadowed by an ext famous “wars” favor Korea and Vietnam, the Philippine-American war was America’s very first foreign “adventure” together a brand-new world power. Politics aside, the conflict was critical milestone in army history, due to the fact that it required the United states to rethink that weapons and also military strategy. 

Warfare in the Philippines

American soldiers battling Moro rebels in the Philippines in 1901. (Image courtesy: Library the Congress)

In the Philippines, American troops were confronted by the Moro tribesmen the the southern islands. The Moro were men of remarkable physical endurance and also savage fighting ability. Fueled by spiritual fanaticism (and probably some nice potent opiates), the Moro involved American troops through brutal guerilla tactics that often contained close-quarters engagement. The tribesmen were typically armed with long, wavy kris knives which showed lethal in combat.  at the time, American troops brought the Colt M1892 revolver together their designated sidearm. However, the revolver’s .38 Colt lengthy cartridge was inadequate for reliably incapacitating this tribal warriors.

In combat, the Moro regularly tied turn off bleeding limbs to protect against blood loss and continued charging, also after gift shot numerous times. their violent and bloody encounters with Moro warriors made the US military realize the requirement for a more heavier round with higher stopping power.


Led by their sergeant through his M1911 in hand, a .30-caliber device gun team the cross a bridge throughout maneuvers in august 1941. (Image courtesy: national Archives and also Records Administration)

In 1906, the United states military started testing several cartridges and also pistol designs because that combat use.  The cartridge that emerged as a clear winner to be the .45 automatically Colt Pistol (.45 ACP because that short). Several pistols were additionally tested, and also Browning’s auto-loading pistol, the Colt design 1911, was officially embraced by the US military just in time for the an initial World War.

The US continued to use the 1911 v Vietnam and much of the Cold War. The Beretta M9 at some point replaced the 1911 in 1985.  However, because of the M1911’s popularity, it to be never completely phased out of army use. Also today, possibilities are an excellent that America’s upstream fighting soldiers have actually a 1911 strapped somewhere to their MOLLE equipment when castle charge right into harm’s way.

Is the Colt version 1911 Still relevant Today?

Today, the 1911 continues to have actually a madness committed pan base. Over there is absolutely some major nostalgia the contributes come its popular (This is the sidearm that aided the United says win TWO civilization Wars!). However, there is an ext to the 1911 and also its .45 ACP cartridge the helps keep its appeal, even in the confront of contemporary advances in small arms technology.

First, the 1911 and also .45 ACP combine to deliver significant stopping power. Back the cartridge produces some pretty splint velocities (usually much less than 900 fps out of the muzzle), the projectiles are large and heavy. The bulk of the projectiles helps create some serious, hard-hitting kinetic energy. With that an effective energy behind it, the .45 ACP penetrates deep and also cuts a pretty wide .45 caliber wound channel together it goes.

Second, the recoil is reasonably tame for such a big caliber. Part even case it produces less perceived recoil than numerous lightweight .40 S&W pistols. The 1911’s mass certainly help absorb several of that recoil. 

Finally, the 1911 renders a practical bring weapon. I understand at first glance, the 1911 looks favor a monster, but hear me out. Also though the 1911 federal government model actions 9 inches and weighs a hefty 3 pounds, the on slide is fairly slim. At less than an inch (.9 customs to it is in exact), the 1911 is significantly more slender 보다 a Glock 17 (1.26 inches). And if you desire to to compare apples come apples, the Glock 21 (chambered because that .45 ACP) is also wider.  that slender profile makes even the biggest 1911 surprisingly basic to carry. The is quiet heavy, so you still could need a good sturdy belt to keep it from dragging your pants down.

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More Than simply .45 ACP


While Browning’s Colt .45 ACP version 1911 is certainly his most renowned pistol/cartridge combo, he is likewise responsible for producing a entirety host of other firearms and cartridges. Many of his pistol loads lug the ACP acronym, including:

.25 ACP.32 ACP.38 ACP.380 ACP

The .50 BMG (12.7×99mm NATO and designated together the .50 Browning through the C.I.P.) was one more cartridge he developed for the Browning .50 caliber machine gun. Browning additionally engineered the 9mm Browning long (9 x 20mm SR), a centerfire pistol cartridge adopted by the Belgian, French, and Swedish military. And also since the isn’t right here to do the bragging, we’ll do it for him v this partial list of Browning’s many notable firearms.


Colt model 1900 and 1902 (.38 ACP)Colt design 1903 bag Hammer (.38 ACP)Browning Hi-Power (9mm Parabellum)Colt design 1903 pocket Hammerless (.32 ACP)Colt version 1908 Vest bag (.25 ACP)Browning BDA Handguns (.38 ACP) (.45 ACP)Colt design 1908 bag Hammerless (.380 ACP)Colt Woodsman pistol (.22 LR)


Savage version 720 long-recoil semi-automatic shotgunWinchester version 1887 lever-action repeating shotgunWinchester version 1893 pump-action repeating shotgunBrowning Superposed over/under shotgunWinchester version 1897 pump-action repeating shotgunWinchester version 1912 pump-action repeating shotgunBrowning Auto-5 long-recoil semi-automatic shotgunRemington version 17 pump-action repeating shotgun


Winchester model 1885 falling-block single-shot rifleWinchester model 1886 lever-action repeating rifleRemington design 8 semi-auto rifleWinchester version 1890 slide-action repeating rifle Winchester version 1892 lever-action repeating rifleBrowning 22 Semi-Auto rifleWinchester model 1894 lever-action repeating rifleWinchester model 1895 lever-action repeating rifleRemington design 24 semi-auto rifleWinchester version 1900 bolt-action single-shot rifle 

Machine guns

M1895 air-cooled gas-operated machine gunM1917 water-cooled recoil-operated an equipment gunM1919 air-cooled recoil-operated machine gunUS M1918 Browning automatically Rifle (BAR)M2 .50-caliber heavy machine gunM4 37mm automatic Gun

Final Thoughts

The Colt .45 ACP design 1911 is just one of the many iconic weapons ever before made, and also we have actually Browning to give thanks to for it. However, the contributions of john Moses Browning expand far past the automatic Colt Pistol.  His early on pump and lever activity designs assisted tame the American West. His military weapons prefer the .30 caliber machine gun and also the .50 caliber M2 adjusted the food of people history.  it is complicated to think that one guy could add so lot to the world in one lifetime. The degree of Browning’s impact is truly difficult to quantify, however we are certainly thankful for it nonetheless.