Category: The Green Machine
Few firearms have captured a nation’s spirit quite like John Moses Browning’s vaunted M1911. Rugged, reliable, cleverly engineered, and utterly lethal, this homegrown handgun is as American as baseball and blue jeans.
Yet, what would the legendary 1911 be without the potent and equally loved .45 ACP cartridge that Browning designed to go with it?
Even though it’s dubbed “the Lord’s caliber” thanks to its widespread popularity – and dare I say, righteous stopping power – I feel we’ve come to take the .45 ACP a bit for granted these days. Here’s a closer look at the story behind a pistol cartridge that helped define American small arms for over a century.
Table of Contents
.45 ACP History
Basic Ballistics & Specs
Pros & Cons
Final Thoughts
.45 ACP History
Developed in 1904, the story behind the .45 Automatic Colt Pistol (commonly .45 Auto and .45 ACP) is tied directly to America’s rise to prominence on the world stage. While the genius of the cartridge came squarely from the mind of Browning, it was actually the U.S. Army that determined the need for a .45-caliber bullet.
This owed much to two factors. First, America’s cavalry at the turn of the 19th century was on the hunt for something to replace the aging Colt Single Action Army revolvers chambered for the rimmed .45 Long Colt.
Meanwhile, a pressing second factor emerged from battlefield experiences during the Philippine-American War (1899-1902) and the Moro Rebellion (1902-1913) in the Philippines. American troops reported poor performance from their smaller .38-caliber revolvers during the campaign.
Frontline reports rolled in, describing harrowing hand-to-hand encounters with enemy fighters who simply shrugged off multiple hits from the U.S. Army’s rimmed .38 Long Colt, which was only recently adopted in 1892. This kicked off a hunt for something new and more powerful.
From the extensive Thompson-La Garde ballistic report in 1904, the army concluded its findings with the following determination: “After mature deliberation, the Board finds that a bullet which will have the shock effect and stopping power at short ranges necessary for a military pistol or revolver should have a caliber not less than 0.45.”
So, the stage was set, and the U.S. Army wanted a .45 caliber projectile similar to the .45 Long Colt already in use with the cavalry. It did not, however, want to return to a slow single-action-only revolver after its intense close-combat experiences in the Philippines.
At the time, Browning and Colt were already working on a .41-caliber prototype cartridge to go with a new semi-automatic pistol design from Browning. They responded to the new request for a .45-caliber cartridge by essentially redeveloping Browning’s handgun design and .41-caliber cartridge. This led to the Colt 1905, which was the first handgun chambered for the new .45 ACP.
Later U.S. Army trials led to the adoption of both Browning’s .45 ACP cartridge and 1911 pistol. Thus, one of the world’s most iconic caliber-gun duos of all time was born. The M1911 chambered for .45 ACP went on to become America’s longest-serving military handgun.
Its military record from 1911 until the mid-1980s made it a household name. But its performance on and off the battlefield made it a legend.
Basic Ballistics & Specs
Like the British .455 Webley, the .45 ACP was a straight-wall design that leaned heavily on the sheer mass of the bullet over velocity to do much of the downrange damage. Unlike the rimmed Webley casing and Browning’s earlier semi-rimmed .32 ACP, the new .45 ACP was a truly rimless cartridge.
Both the straight wall and rimless profile were meant to help the .45 ACP function specifically inside semi-auto firearms that fed from magazines instead of cylinders. At first, the Colt 1905 was tested with 200-grain bullets, but this was increased to 230 grains for what became the standard .45 ACP.
Before we dig into muzzle velocities and other data points, it’s worth highlighting that the U.S. military was very, very interested in terminal performance over simply specs. To that end, the Thompson-La Garde Tests from 1904 took a rather gruesome turn with testing on live animals.
This included a head-to-head comparison of the effects of close-range fire on living cattle with a .45-caliber projectile and a rising star in the 9mm Luger. Here are two brief but graphic excerpts of the results:
Blunt .45 Caliber: “9:46:30 A.M. Animal shot through lungs from left to right; fell to the floor at the sixth shot. Hemorrhage was free from one of the perforations in the right side. The animal was very much excited and kept jumping from side to side until she fell to the floor. Death occurred at 9:49 A.M.”
9mm Luger: “10:15 A.M. Animal was shot from left to right. There was an interval of one minute between the second and third shots, due to a hitch in the working of the pistol.
At 10:18:15 A.M., when the animal had been shot eight times, there was a short interval on account of reloading the magazine. Two shots were fired through the abdomen; at this time the animal was bleeding from the mouth.
After twelve shots had been fired the cow was still standing and had to be killed by the hammer. Ten shots were fired through the lungs and two through the abdomen in this experiment.”
As gruesome as the testing was, the clear impression left on the U.S. military was that the hefty .45 delivered with its heavy weight what the 9mm couldn’t with higher velocities. That terminal performance is still largely represented in the basic ballistics of modern 9mm and .45 ACP ammunition.
Here’s a quick comparison of basic, 124-grain 9mm FMJ and 230-grain .45 ACP FMJ.
You can also compare the .45 ACP stats from above to the rather anemic black-powder 150-grain .38 Long Colt, which offered velocities ranging from 650 to 750 fps. That put it at a mere 140 to 187 foot-pounds of energy. Even the switch to modern smokeless powder only bumped velocities to 750-800 fps. That left it at a relatively low 187-213 foot-pounds of energy.
For the modern shooter, there’s another benefit to the .45 ACP’s slower velocity. The increasing popularity of suppressors benefits from the subsonic speeds generated by the .45 ACP. Normal muzzle velocities for the .45 ACP generally fall between 800 and 900 fps, staying well below the speed of sound (1,125 fps at sea level in 68 degrees Fahrenheit).
Since this slow-flying bullet has enough mass to make up for its velocity, there’s a good reason .45 ACP is a popular suppressor round for handguns and pistol-caliber carbines. This quality was well known to gun designers in the 20th century, with firearms like the integrally suppressed British De Lisle commando carbine using the slow-moving .45 ACP as a quiet sentry killer in World War II.
Pros & Cons
Here are my top five pros and cons for the iconic .45 ACP. Keep in mind that modern specialty loads can vary greatly, so these are only based on the most general characteristics of the cartridge.
Pros:
- Strong terminal ballistics due to heavy weight
- Suppressor-friendly velocities
- Reliable semi-auto design
- Common and easily found caliber
- Over 100 years of proven performance
Cons:
- Large size lowers magazine capacities
- More expensive than 9mm
- Low velocities for longer ranges
- Usually more recoil than calibers like 9mm
- Heavier overall weights for carrying
Final Thoughts
The sheer number of 1911-type firearms still in production, with new variants arriving every year, is a solid testament to just how much America is still in love with Browning’s design. The .45 ACP remains a part of that legacy.
I have no doubt the caliber debate will continue to rage well beyond even the modern era’s “9mm vs. everyone else” trend. As for the classic .45 ACP, I can’t imagine it leaving the American marketplace in my lifetime. Anything is possible, but I think there are too many shooters who love the round for its history and performance to let it just fade away.
In fact, it’s still well-respected for its terminal performance and suppressor-friendly qualities. That has kept it as a go-to option for many law enforcement groups and private citizens. It’s also still a common feature inside Special Operations arsenals, even if its general military use has largely waned.
The “Lord’s caliber” gets the job done.
The Battle of Caloocan was one of the opening engagements of the Philippine–American War, and was fought between an American force under the command of Arthur MacArthur Jr. and Filipino defenders led by Antonio Luna in February 1899.
American troops launched a successful attack on the Filipino-held settlement of Caloocan on February 10, which was part of an offensive planned by MacArthur Jr. Occurring a few days after an American victory near Manila on February 4–5, the engagement once again demonstrated the military superiority that American forces held over the Philippine Revolutionary Army.
However, it was not the decisive strike that MacArthur had hoped for, and the war continued for another three years.
Anyone who ever flew an Army helicopter reveres the Loach. Uncle Sam called the bizarre little egg-shaped aircraft the OH-6A Cayuse. Its official classification was Light Observation Helicopter, hence the informal appellation “Loach.” The Loach looks and sounds like a giant, angry bumble bee. It is a simply magnificent machine.
The Loach was used for scouting missions during the Vietnam War. The aircraft was flown without doors at extremely low levels. The typical crew layout was a single pilot on the right with a crew chief sitting just behind on the same side, packing an M60 belt-fed machinegun suspended from a bungee cord. Offsetting the weight on the left was an M-134 minigun in an XM21E1 mount. This electrically-powered 7.62x51mm belt-fed Gatling gun cycled at either 2,000 or 4,000 rounds per minute via a two-stage trigger. It fed from a 2,000-round ammunition magazine. The pilot sighted the minigun via a grease pencil mark on the inside of the Plexiglas canopy.
The Loach operated most commonly as part of a Pink Team. In this configuration, the Loach cruised about down low in the dirt, looking for bad guys, while one or two AH-1G Cobra gunships orbited at altitude, waiting to dive in at the first sign of trouble. The two elements maintained constant radio contact. Experienced Pink Teams were devastating killers on the battlefield. Survival and tactical effectiveness demanded both nerves of steel and exceptional pilotage.
Of all the scout pilots who served in Vietnam, one name percolates above all the rest: Lt. Col. Hugh Mills. He is a legend among Army aviators, even today. A Loach painted as his distinctive “Miss Clawd IV”, dangles proudly from the ceiling at the Army Aviation Museum at Fort Rucker. Among rotary-wing aviators, that is the Army’s highest accolade. Lt. Col. Mills earned every bit of that love.
A Hard Day in Hell
In the summer of 1969, then-Lieutenant High Mills piloted his agile little Loach as the bottom half of a hunter-killer Pink Team. In the back was his regular crew chief, Jim Parker. Mills and Parker had flown together for months and were forged into an exceptionally effective scout team. On this fateful day, they were clearing the route for a supply convoy along a length of highway called Thunder Road.
Without warning, Mills’ Loach was engaged by a well-sited VC .50-caliber machine gun. One of the big thumb-sized rounds punched through the leading edge of one of the Loach’s four rotor blades about four feet from the tip. There resulted a skull-crushing vibration as the hearty Loach clawed to stay in the air.
Mills retained control of the stricken aircraft, but only just. He guided the doomed helicopter to a controlled crash on a nearby flat piece of rice paddy. Parker split his chin on the front sight of his M60, but both aviators were otherwise unhurt. They cleared the aircraft with Parker’s M60 and a seven-foot belt of ammo along with Mills’ CAR-15 and a bandoleer of magazines.
Mills spotted a pair of VC soldiers shooting at them with AK-47s from about 175 yards away. He fired a burst from his CAR-15 as Parker sprayed the area with his M60. Both enemy soldiers fell, but they just kicked over the anthill.
A substantial VC force began slathering the crash site with fire and moving toward the two trapped aviators. Parker returned to the crashed aircraft to retrieve more M60 ammo as Mills covered him with his CAR-15. Meanwhile, the high-cover Snake pummeled the tree line with 2.75″ rockets and minigun fire. However, the Cobra soon ran out of ammo.
Just when it seemed like all was lost, a nearby Infantry Brigade commander in a command-and-control aircraft dropped down to make an emergency extraction. Parker and Mills clambered aboard the hovering Huey and made their escape before the remaining VC could stop them.
Turning an NVA Pot into a Colander
During that same summer, Mills and Parker were tearing along in their Loach on a routine trip into Dau Tieng for a briefing. They had a G-model Cobra flying top cover. As they pitched over a ridgeline, Mills surprised an NVA heavy weapons platoon on the march. Without hesitation, he opened up with his minigun at close range as Parker unlimbered his M60. The NVA troops answered with a fusillade of AK-47 fire.
A pair of NVA soldiers tore off down a paddy dike toward the wood line and cover. The nearer of the two enemy soldiers carried a big cooking pot that flapped against his back as he ran. Mills quickly pivoted his nimble little aircraft, lined up the grease pencil mark on his canopy and triggered a quick squirt from his minigun. His burst passed through the nearest NVA soldier and into his buddy, killing them both.
Mills chased the remaining NVA troops around the paddy until both he and Parker ran out of ammo. Parker then unlimbered both his M16 as well as a 12-gauge pump shotgun. Meanwhile, Mills steadied the collective lever with his knee and emptied six rounds left-handed from his personal .357 Magnum revolver at the fleeing enemy troops. Once completely out of ammunition, Mills rolled clear so the orbiting Snake could pulverize the area with 2.75″ rockets packing flechette warheads.
In two minutes of unfettered combat, their Loach had been hit 25 times. The airspeed indicator and altimeter were both blown away, and the armor plate underneath Parker’s seat had caught two rounds. Mills’ seat armor stopped several more. Five rounds shattered the Plexiglas canopy, two hit the tail boom, and another three struck the rotor blades. One AK round transited the engine compartment but missed anything significant. Another shot the op rod off of Parker’s M60.
Supporting ARP (Aero Rifle Platoon) grunts subsequently inserted and swept the area. They cataloged 26 KIA and seized a pair of POWs along with a large number of AK-47 rifles, an SGM heavy machinegun, a 60mm mortar and a pair of Russian pistols. When they returned to base, the infantry troops presented Lt. Col. Mills with a cooking pot sporting 24 bullet holes.
The Rest of the Story
While serving three combat tours in Vietnam, Lt. Col. Hugh Mills earned three Silver Stars, three Bronze Stars, four Distinguished Flying Crosses, and the Legion of Merit. He was shot down an amazing 16 times and was wounded three times in combat. He ultimately flew 3,300 combat hours in OH-6A and AH-1G helicopters. His record as a combat aviator will never be bested.
The OH-6A was tragically replaced by the Bell OH-58 in Army service. Both aircraft shared a common engine, but in my opinion the Loach was a massively better aircraft. I flew OH-58’s myself, and we all mourned the passing of the Loach. However, that was not the last Uncle Sam saw of this extraordinary little machine.
The Task Force 160 SOAR (Special Operations Aviation Regiment), better known as the Night Stalkers, adopted the OH-6 in an upgraded form as the MH-6 Little Bird. They call it the “Killer Egg.” These immensely capable machines feature an upgraded powertrain along with a more efficient five-bladed rotor system. The Night Stalkers use both an armed gunship version of the aircraft as well as slick-sided variant designed for covert insertion of special operators in places where stealth and speed are of the essence. If ever I win the lottery, my first call will be to my wife. My second will be to Boeing to pick up an MH-6 of my own.
Lt. Col. Mills penned a book about his exploits in Vietnam titled Low Level Hell. It is an amazing read that is just packed with action along with plenty of cool commentary about small arms. It is available on Amazon.
Categories
One of my favorite rounds – The 44 Magnum
Nothing like putting something aside for a rainy day! The Marines did that after WWII and that stuff came in mighty handy when Korea lit up 5 years later! Grumpy
FADE IN:
EXT. COF, 618TH ENGINEER SUPPORT COMPANY (AIRBORNE) – 1745 HOURS, FRIDAY NOV. 10
WE OPEN outside the company operations facility, late on Friday afternoon, after three days of searching for the company executive officer’s Humvee, which disappeared without a trace on Tuesday night. The disappearance derailed the company field exercise, and leaders are furious. The shot begins wide, capturing the entire company formation and the building’s facade, before it slowly pushes in closer on the man standing in front of the unit.
As we draw nearer to him, it becomes clear that the FIRST SERGEANT isn’t mad. He’s just (visibly) disappointed. And maybe a little afraid?
FIRST SERGEANT
Ok, 618th, on the command “fall out,” I want you to form a school circle around me, hooah? It’s been a long week, so let’s make this quick and enjoy the long weekend, hooah?
Scattered “hooahs” emanate from the beleaguered paratroopers.
FIRST SERGEANT
Fall out!
BEHIND THE FIRST SERGEANT
The soldiers quickly assemble around the FIRST SERGEANT. Noticeably absent is the COMPANY XO.
FIRST SERGEANT
Listen up, paratroopers. As we all know, someone stole Nasty 5′s Humvee while we were in the field earlier this week. The LT and the CO are currently in the brigade commander’s office.
FACING THE COF, SLIGHTLY ELEVATED TO SEE FIRST SERGEANT OVER THE SEA OF SHOULDERS
FIRST SERGEANT
It’s been a tough three days. We’ve combed damn near every training area on this post.
FIRST SERGEANT
If anyone in this company knows anything about where the LT’s Humvee is, please step forward now. Let’s end this here and now. I can offer amnesty — no harm, no foul, no negative consequences.
BEHIND FIRST SERGEANT, LOOKING OUT ON TROOPS
Nobody steps forward. A few junior enlisted soldiers exchange suspicious glances, but it’s not clear whether they plotted the theft or whether this is just how they act all the time. Really could be either.
CLOSE UP OF FIRST SERGEANT’S FACE
The FIRST SERGEANT pauses, grimaces and shakes his head as if he’s choking on the words that come next.
FIRST SERGEANT
Please.
Several seconds of silence follow. The specialists in the back continue exchanging suspicious glances, and now it’s certain that this is just the way they are. Or is it?
FACING THE COF
FIRST SERGEANT
I’m serious, please return the LT’s truck. If this is a prank, it is no longer funny. Hell, it stopped being funny two days ago. Return it now, and it can be funny again! Please, guys. Please.
The soldiers shift back-and-forth uncomfortably. They sense something bigger might be at play here. The FIRST SERGEANT, visibly nervous, checks his watch — the biggest, chunkiest, most stereotypical rubber impact-resistant watch ever seen on Fort Liberty.
FIRST SERGEANT
You don’t understand what’s going to happen if we don’t find this Humvee by 1800. Any soldier who is man enough to come forward now and admit stealing it — or to tell us who did it — will receive four-day special pass for next weekend as well.
Nobody moves or speaks up. A DISGRUNTLED SPECIALIST IN THE BACK groans audibly.
FIRST SERGEANT
We are running out of time to solve this problem ourselves. I cannot save us from anything that happens next — unless one of you comes forward. Please, guys. It’s Friday of a long weekend. Today was supposed to be a DONSA. My wife has called me six times in the last 30 minutes.
The FIRST SERGEANT’s elaborately shock-resistant, waterproof watch beeps.
CLOSE UP OF CHUNKY WATCH
The watch reads 18:00, because of course the FIRST SERGEANT’s watch is set to 24-hour time. A vehicle engine sounds in the background as a lifted pickup truck approaches.
FIRST SERGEANT
Please! Just give us the LT’s Humvee. If you come forward in the next 30 seconds, you’ll also get out of our next red cycle tasking.
FACING OUT FROM COF, STREET IN BACKGROUND
The doors of the lifted pick-up truck open, and five people get out. It’s not clear how they all fit inside. The BATTALION CSM, two CID AGENTS wearing marked civilian clothes, the COMPANY COMMANDER and the COMPANY XO (who looks like he hasn’t slept since Tuesday) emerge and walk toward the formation.
As the soldiers realize what is happening, they turn around to watch the group approach.
INTERCUT BTWN BATTALION CSM, FIRST SERGEANT, COMPANY COMMANDER and COMPANY XO
BATTALION CSM
First Sergeant, any luck?
The FIRST SERGEANT shakes his head to signal no. The BATTALION CSM appears a little too excited about what’s going to happen next. The COMPANY COMMANDER sports a 1,000-yard stare. The COMPANY XO — wait, is the XO crying?
TRACKING SHOT follows the BATTALION CSM, who is flanked by the CID agents, as they walk to the front of the gaggle formation. (DW note: Not sure if the Imperial March is appropriate for this scene or not, remember to discuss with director.) Camera settles back in FACING THE COF once finished tracking.
BATTALION CSM
How we doing, Nasty Company? You had your chance to do this the easy way. Here’s what is going to happen now.
The BATTALION CSM gestures toward the two CID AGENTS. He pulls out a stack of papers — rights waivers, required for witness and subject interviews. One of the agents appears to mouth the word “sorry” as he stares intently at his feet.
BATTALION CSM
These two gentlemen are going to interview every single soldier in this goddamn company. Yes, you have a right not to speak to them. I don’t care. Every one of you will either sit with them in the COF or sign the sheet saying you refused to speak without a lawyer present. The good news is that Trial Defense Services is able to help those soldiers. The bad news for all of them is that TDS is out of the office until Tuesday, and you are under orders not to leave this company footprint until you and your lawyer complete an interview, hooah.
Absolutely nobody echoes the hooah. The COMPANY COMMANDER slinks into the COF. He probably was going to stay there all weekend sending emails anyways.
BATTALION CSM
But don’t any of you think that doing a one-and-done interview will get you out of this either. Every day this weekend, from 0600 to 1900, the XO will be leading the entire company in a “Hands Across America” police line through the Mott Lake training area — including the water. You will either find this Humvee or drown trying.
QUICK CUT to the COMPANY XO, who is sitting on the ground behind the formation hugging his knees and rocking back and forth, shaking with each successive sob. The crying grows gradually louder even after the camera cuts back to the BATTALION CSM.
BATTALION CSM
OK team, that’s all I have. I’ll be with you this weekend because I don’t like my family anyways. You have 30 minutes for chow; someone bring me a Popeye’s chicken sandwich from the Butner Road shopette. Stay Nasty!
Soldiers scatter and begin calling their families to relay the bad news.
FADE OUT
Observation Post is the Military Times one-stop shop for all things off-duty. Stories may reflect author observations.
Davis Winkie covers the Army for Military Times. He studied history at Vanderbilt and UNC-Chapel Hill, and served five years in the Army Guard. His investigations earned the Society of Professional Journalists’ 2023 Sunshine Award and consecutive Military Reporters and Editors honors, among others. Davis was also a 2022 Livingston Awards finalist.