Here’s an unpopular opinion — the 9mm vs .45 debate is a non-issue. This hotly debated topic has been talked to death. Among these two calibers, only one makes up the majority of the world market share of ammunition but both cartridges cater to a very loyal user base due to each calibers’ successes in multiple fields. 

Don’t worry, we’ll still get into the nitty gritty as to why this has been so hotly debated. By the end of today’s blog you’ll understand what we’re talking about. 

9mm vs 45: What’s the difference? 

Some think that the two calibers were developed in different times for different purposes but that’s actually not true. Both calibers were designed to be effectively lethal cartridges at relatively short distances prior to the first world war. 

9mm vs .45: Military Service

The .45 ACP is revered as a classic American caliber for its roots dating back to the civil war from its predecessor, the long .45 Colt cartridge. Its successor, the .45 ACP, that we know and is still loved by many today, was developed in 1904. You’d typically find .45 ACP being sold with full metal jacket bullets weighted at 230gr and it’s actually continued to be sold that way for over a hundred years now. 

The 9mm was developed two years prior to the .45 caliber by an Austrian designer named George Luger in 1902. Both calibers went on to serve in World War I and World War II. Even though it had only been a couple years since its initial development, by the time WWI broke out there were already submachine guns chambered for 9mm that were being issued for the German military’s use. 

You’ve probably seen the jokes and the memes online about the M1911 chambered in .45 winning America two world wars. While there may be some merit to the meme, times change. As early as 1955, the North Atlantic Council had chosen the 9mm to be standard caliber for sidearms issued for NATO forces. Most of Europe at that point was sporting the Browning Hi-Powers chambered in 9mm so it was a practical decision. NATO’s adoption of the 9mm caliber also made sense logistically in the event there was another major war, supplying ammunition to allies would not be as difficult. 

It was a few decades later until the U.S. decided to also adopt the 9mm when the M9 Beretta finally relieved the 1911 of duty in 1985. Since then, the M9 Beretta has been in service of the US Armed Forces until recently when it was relieved of duty by the Sig M17. Although the handgun model has changed, the caliber of choice is still 9mm.

However, the M1911 and M1911A1 chambered in 45 stands to be the longest serving sidearm of the US Military (and for good reason) as it was used from 1911 to 1985 – 74 years!

9mm vs. 45: Ballistics

.45 acp springfield 1911

Before you jump into conclusions, why don’t we let the science speak for itself. Just because the .45 round is bigger than the 9mm doesn’t mean it’s necessarily better. 

.45 Ballistics

Blackhills 9mm and .45acp shot and tested in ballistic gel

There’s a saying, “I carry a .45 because I don’t like to repeat myself.” Ever heard of it? Sure there is a lot more kinetic energy behind a .45 projectile and that is desirable in a premium defense round. However, take a look at the image above. On the top is a Black Hills 9mm projectile and the bottom is a Black Hills .45 ACP +P projectile. The wound channel is certainly larger but doesn’t have as much penetration as the 9mm round (short by about an inch). 

Proponents of the .45 caliber will say that they prefer the bigger round because it would have a higher possibility of hitting a vital organ. With only that reasoning, sure that’s hard to argue against. But factor in this — According to the FBI, law enforcement officers miss anywhere between 70 – 80% of their shots fired during a shooting incident. Hard to win a firefight if you only have seven to eight rounds in a magazine no? 

From an Executive Summary of Justification for Law Enforcement Partners issued by the FBI, they’ve also debunked the myth of “handgun stopping power” because the single most important factor in wounding a human target is to have bullet penetration of anywhere between 12” – 18” per the Bureau’s standards. The .45 ACP certainly meets that standard, but so does 9mm with a variety of different weight projectiles. 

Studies of “stopping power” are moot because it turns out that no one has actually ever been able to scientifically define how much kinetic energy is required to effectively stop a determined and violent combatant. 

9mm Ballistics

ballistics chart with 9mm and .45acp

According to the senior ballistician at Hornady Manufacturing, there’s now very little difference in the terminal ballistics of premium self-defense rounds between 9mm and .45 projectiles that are tested with ballistic gel. So if there isn’t that big of a difference ballistically, but the 9mm is easier to shoot and handle, why choose the .45? 

If you go on Youtube or Facebook Videos, it’s easy to find videos of police officers mag dumping either caliber into people charging at them. The reality is that both calibers are not effective means of stopping combatants who are under the influence of drugs or alcohol which significantly delays the effect of pain unless a shot is placed on the person’s central nervous system; i.e. their brain. 

9mm vs .45: Which is better for competition?

2011 STI combat master chambered in 9mm

Not everyone has the wrist strength of God Himself like Jerry Miculek. For him, caliber probably doesn’t matter but he’d probably never let on how much a caliber hurts to shoot. He’d just say, “yeah that kicks.” .45 can increase your confidence in knocking down steel plate targets a lot more but if you’re mostly expecting to be going up against cardboard targets, you might prefer the double stacked magazines that 9mm guns will have.

Unless you’re a professional competitor, the 9mm is probably going to be the better choice for the longevity of your wrists and perhaps even career as a competitive shooter. Although there are 2011’s made for .45ACP most of them are offered in 9mm, if that tells you anything. 

9mm vs .45: Price Comparison

Since the 9mm makes up most of the world production of ammunition, it should be far more available (depending on where you live) and is therefore a cheaper and more practical alternative for those looking to spend a lot of time on the range. However, due to the major ammunition shortage that started in 2020 and price hike we’re still experiencing now, it has significantly closed the price gap between the two calibers.

Here are some more reasonable prices we recently found of ammo retailers providing 9mm and .45ACP:

9mm seems to range anywhere between .37 – .57 cents per round depending on if you’re able to make a purchase in person at a store like Bass Pro, Academy or if you choose to buy in bulk online.

.45ACP seems to range anywhere between .55 – .60 cents per round.

*These prices were accurate up to the date this article was published on July 20th, 2021.

Our Recommendation

So why do we think this issue is actually a non-issue? Well, we simply don’t live in a time where this topic is as fiercely debated anymore. At this point, gun owners and professional users alike that sport .45 caliber pistols will likely do it out of tradition more than performance. Now that’s not to say there can’t be highly tuned and extremely fast performing guns chambered in 45… because there most certainly are. 

For competitors it makes sense to want to be able to compete in the “heavy” division which is where 1911/2011 race guns live and shoot the .45 caliber. If you have a job that requires you to be armed with a handgun, chances are it’s going to be chambered in 9mm. It’s more rare now to see .40S&W pistols be issued to officers but it does happen. However, along with all the aforementioned factors, when you consider the FBI’s switch back to the 9mm since 2015, the overall answer to this debate seems to be pretty clear.

The reason why this debate persists is because everyone’s shooting needs and abilities are different, therefore the differing opinions. But in general, if you’re looking to shoot suppressed, the .45 ACP is the better and quieter option as it shoots much slower, heavier subsonic rounds compared to 9mm. For those wanting to have a handgun for self-defense, 9mm is the clear winner for its ballistic capabilities, higher mag capacity and very manageable recoil. If you like owning multiple guns and don’t have a budget restriction, just get multiple handguns chambered in each caliber; problem solved.