5 Reasons You DON'T Need A 45 ACP 

As a .45 ACP carrier I have ONE factor that most overlook. I live in Massachusetts. There is something to be said about carrying a gun that both complies with the 10 round mag limit, and complies with it from the gun's inception, and that new magazines are readily available. If I am mandated to carry 10 rounds, I'd rather they be ten BIG rounds rather than 10 smaller rounds in a magazine that has been retrofitted to only hold 10.

As far back as 1961, the Late Colonel Cooper, as much as he praised the .45 decried the government load 230 hardball. He chastised the Army brass for specifying the .45 ACP duplicate the ballistics of the .45 Schofield instead of the .45 Colt. Cooper himself taught that government hardball be limited to practice ammo. He specified what was then referred to as "Super X" Loads which today we call "+P". His initial loads were 200 GR lead SWC's loaded to 965 FPS later going to 230 GR truncated conical bullets once again loaded to 965 FPS. Basically, light .45 Super

You can contol tecoil if you train with it a lot. And ironically, due to me shooting the 1911 longer and far more rounds, my shooting with the nine is faster and my reloads are far quicker. I have steel frame 45s that soak a good bit of that energy so my followups are pretty quick. Its fun to shoot and its a classic and great looking gun. As farcas carry though, its a boat anchor, however when carrying a micro or sub compact you run into the exact same mag limitations. Oh well good vid as always. But plastic frames is not what it was intended for.

I’m so glad I found this channel. 9 for EDC but I also keep a 45 backup too, mostly because it’s fun.

The 45 acp is a man stopper. In especially a military environment, it is far more effective since you are limited to FMJ rounds. Bigger round = bigger hole and much more energy being dumped into the soft fleshy target. It also is less likely to over penetrate.

Unfortunately I live in a 10rnd mag state, so if I can only carry 10, might as well be 45

Got a USP rigged with 45 Super. A very good compromise if you like the size of a 45 but want that speed. Buffalo Bore and Underwood both sell ones that go up to 1300fps. If you hand load you can get it even faster.

Firing a 45ACP with a 230gr bullet launched at 900fps gives you 413 ft lbs of energy. It works. I fired 45AC in competition years ago. I have SO much used brass, I will never to buy more. You can reload that brass almost forever. I cast my own soft lead bullets and gathered the lead sheeting from a dental office demo job from the x-ray room decades ago. I also sift my berm/backstop on my range periodically to reclaim lead. Primers and powder, prepared long ago for not being able to find them. Carry an extra mag or two and you have enough ammo for a 1911. The pistol is not a primary arm, to me. Shotguns and rifles occupy that category for me. I keep using a 1911 because I have a bunch of them and they are all paid for, I know them extremely well, and I have decades using them. They work. Use what you like and be a good shot. All cartridges can kill, even a 22LR. Exercise situational awareness and situational avoidance. Get your preps in order. Time is short for what is coming.

As a Californian, I appreciate the 9mm. My primary is a CZ 75 SP-01. HOWEVER: my first handgun was a RIA GI 1911A1. Why? Magazine restrictions. I could (and did) buy 10 round mags for my 1911. I always HATED 9mm handguns because the majority I handled were polymer frame guns. Some even had trigger bite. Not fun. About 6 years ago I packed up my 1911A1 and traveled to Utah for 4 years. In that time I picked up two .22lr rifles for under $200 each and bought myself the CZ. I LOVE that gun. Unfortunately, during that time I fell on economic hardship so I sold my 1911. It was a bit of a loss when considering the 3 10 round mags, but it helped pay the rent. Today, I miss my .45 Auto. Don't get me wrong, I love my CZ, but I was actually more accurate with the stiff, heavy recoil of the 1911 than I am with my CZ's slightly snappier and sudden recoil. Legally-speaking, I can only carry 10 rounds of either, too. Guess which one I would prefer to have available if someone breaks in my door? Sorry not sorry, I really wish I had the .45 back. Again, there are absolutely advantages of the CZ. The recoil IS less, but it's harder to recover from than the 1911. It is capable of up to 18 rounds, but California happened. The ergonomics are just slightly better on the 1911 than the CZ, but that's not a big factor when I have the under-barrel rail built into the CZ so I can always have my flashlight attached. Ammo is cheaper in 9mm by far, though you wouldn't be able to tell that with Cali prices and the background check here. Finally, in a completely non-objective way, I have to say I think the 1911 is just way prettier. I had the bog-standard parkerized GI model with wood grips and I will never say that my CZ that cost over $100 more is better looking. It IS sexy with its slim slide and glowing sights, but it's still not as pretty as a regular 1911. Also, a guntuber with a bass voice gets an auto thumbs-up from me. We aren't represented well enough in the community. Brandon, Scott, Ian, Matt, they're all a bit higher register. It catches attention. It's more exciting. The low voice though? We cause relaxation and pause. In fact, you're getting a sub for something you can't change. Excellent video!

I have a Gen V G21 with a 6.2" SS threaded barrel. I run +P 230 HP's suppressed and this thing is a monster..... I would NOT want to be on the receiving end of it. Run a long mag in it and it's an excellent home defense weapon. Still Hearing safe, no loss of night vision (flash is suppressed) and tons of stopping power but not going to kill a family member after going through 2 or 3 walls....... Also, I'd submit there really isn't any more felt (negligible) recoil from the +P load with the suppressor hanging off the front. Just my $ .02.....

When the military requested a round powerful enough to "Falter a horse" and BROWNING said "Challenge Accepted" This was when the best combat sidearm round to ever be devised was born.

We won 2 WWs with this and the 30/06. We have pretty much been ran out of every conflict since.

I saw some high-speed photos of a .45 ACP, 1911, and it was pretty clear that recoil does not start until after the bullet leaves the barrel. The recoil is mainly due to the fact that after the bullet leaves the barrel you’re holding a rocket in your hand. I carried the 1911 when I was on guard duty in the Navy. The problem we had then was the weapons were quite old and we had to be very careful handling them. Also, they lacked a magazine safety. If you’re going to go with that caliber, I recommend something more modern. I think a key thing to consider is how accurate a person can be with a particular firearm. I can reliably hit apple-sized targets from the hip at ranges up to about 25 yards using a 1911. Overall, I qualified expert while I was in the Navy. That is one thing that I’ve heard from a lot of people who carried the 1911. While all the facts you have presented are very useful, it comes down to what a person can handle and what a person can use.

Change the grain weight from 230 to > 200 or 190 and 45 would be perfect

Effective Self-Defense 1. Hitting the Critical Areas requires: Reliable, accurate handgun High Degree of shooting skill 2. Effective wounding requires: Large permanent cavity (hole) from Big bullet diameter and/or Reliable expanding bullet(keeping in mind, that a smaller bullet will not get larger than a bigger bullet) Deep penetration Heavy bullet 3. Multiple Hits

Momentum = force = knockdown/stopping power. Usually measured in ft/lbs of energy. Sometimes velocity can make the difference, but usually only with penetration. Hence the deeper penetration as seen in your 5.56 vs 6.5 Grendel with the 3/8” thick steel plate.

You made your decision and Ill make mine.

I carry 45 and 9mm ,45 is my favorite in 180 grain,also I make ammo for a living and all my coworkers really like all 3 cartridges you mentioned.to each his own .

Meh... 1. Weight. A consideration for the military who has to transport millions of rounds, all around the world. Insignificant to a defensive carry handgun. Not even an issue. Next... 2. Capacity. Meh...the capacity of even a single stack .45 ACP is _enough_ for personal self defense. The chances of settling a self defense issue with 9, 10 or more rounds that couldn't be settled with 8 is virtually 0. 3. Power. It is powerful enough for personal self defense. The main purpose of such a gun is "attitude adjustment". You want to be a harder target than the guy who plans to call 911 in an emergency. Shot AT someone and miss, or wound them and they run away...YOU WIN! A self defense gun usually makes an assailant go looking for an unarmed victim. 4. Recoil. The .45 is for big boys and girls. I agree with you, the 9mm is for p*ssies. 5. Cost. I handload. Costs virtually the same for all cartridges, depending on the bullets you choose. For practice ammo I cast my own bullets from a decades old stockpile of wheelweights...so MUCH cheaper than factory "practice" ammo of any caliber. Ammo "cost" is what YOU make it. I choose not to be held hostage by the ammo companies and their "shortages". Good video. 👍

Good video, coming from a 45 ACP fan.

civil defense ammo ftw! you gotta love how light those rounds are so much that i use them in multiple calibers for edc. almost makes it a moot point with the weight and speed issues

But for real tho. The 9 is definitely weaker than the 45. The box is always full of crap. The 9mm is going a little faster than the 45, but it truly hits a lot harder. Check the data. The military didn't dump it completely as socom still uses the 45.

I really enjoy your videos, you do a really great job demonstrating your points with real world shooting. I've thought the same thing about .45 ACP for a few years now since I started reloading for my father's Colt .45 in AutoRim (functionally ACP) and noticed the muzzle energy is actually just a tiny bit more than 9mm. Shooting the Colt .45 revolver is a pleasure though, and it's heavy enough out front that it seems to have about the same felt recoil as my Ruger P85 9mm. Note it's not 45 Colt...... it's .45 AutoRim. Unfortunately .45 AutoRim cannot be used on either .45 Colt (long) or .454 Casull due to it's very thick rim. .45 Colt was surprisingly tame as well and I have no desire to run it in my Casull, makes the Casull feel like a .22 cal.

The spirit of John Browning made it rain on you. Two world wars man.

The military went to 9mm and within a couple years almost every Spec Ops went back to the .45 .

We really need to see sound meter db levels to come to any conclusion about the differences in sound between the rounds. Can't make out much the way they are compared here.

I served with some guys who had been in the sh*t - who had used the M1911 and the M9, and their personal carry guns were .45, and that is good enough for me. The _only_ reason I switched (during the Clinton years) from .45 to 9mm was price - can't hit under pressure if you can't practice often and remain proficient.

To sum up, the 9mm has more horsepower than the .45 with little to no torque. But the .45 has much more torque.

The 10th commandment was actually mistranslated. It actually says everyone should have the Lord’s caliber, 45 ACP.

I’ve been using my Hybrid46 on my USP45T and it’s been flawless for at least 1000 rounds. Sights are at the exact height of the suppressor so you can make accurate shots, but you do lose some lower view

In my opinion, it's just mine, .45ACP is a bit much for a carry gun. If it's a CCW that is. I personally am partial to .380ACP. Why? To me, .380ACP is the modern day .38 Special. It's soft shooting, so accuracy in high stress situations should be higher. If you practice on a heavier hotter cartridge, carrying something lighter should mean you'll be even better with it. My .380ACP is smaller than my full size 9, yet it both recoils less and I shoot better. .45 is a great cartridge for all sorts of things! It's great for wilderness defense (though then some would argue you should be carrying 10MM instead), and it does pack a good punch. In most situations though, why not just carry a 9mm? 9mm isn't what it used to be...it's better. When .45ACP and 9MM were both around at first, .45 made much more sense. bigger diameter, more grains of gunpowder, and using ball ammo, it made sense. 9MM's stopping power wasn't fantastic. Today though, we have hollow points, rounds loaded hotter than they were, and capacity in 9mm that .45ACP can only dream of. I personally would rather run a .357 Magnum snubby than a .45ACP, if I'm going to run a gun that's low capacity, I want simplicity and ease of carry. Revolvers have that in spades.

Yeah, well... The unexpanded diameter of my 45 auto, Underwood Xtreme Dedender, is but the goal diameter of a 9mm fully expanded.

What one says I don't need is negated by what I prefer... 357 magnum and 45 acp are my preferences that fulfill my needs just fine... It can be argued most will never actually need to use a gun, ever... But if I ever do, I decide how big I want the hole to be, not some youtuber...

I guess we should dump knives. Old technology.

New subscriber - great vids. Thanks. Looking forward to seeing more of your vids and anyone ones! (Old geezer & lifelong hunter and target shooter.)

Oh my it takes 15 rounds of 9 mm to do the same thing the three rounds of 45

The .22LR from a pistol barrel is 200 feet per second slower (and more) than the same cartridge fired from a rifle barrel. Even high velocity .22 LR from a Ruger Mark I pistol barrel (4-3/4") clocks subsonic over my chronograph. That places the .22 LR pistol between a .45 ACP pistol and a 9mm NATO pistol in muzzle velocity. It's a common mistake because most factory .22LR ballistics tables are made with a rifle--length barrel. From a rifle, the supersonic .22LR loads are close in muzzle energy to the .32 ACP. A forgotten fact is that John Browning designed his .25 ACP to produce the same impact as a .22 LR fired from a pocket revolver. Speaking of the tiny .22 pistols with very short barrels, those pistols may have muzzle velocities down around 800 feet per second, about 2/3rds of what the same cartridge would generate from a rifle barrel. Energy of a .22 LR bullet fired from a derringer is going to be half of the same cartridge fired from a rifle barrel. Barrel length matters for noise reduction, flash reduction, and muzzle velocity.

The 45 seemed to edge out. Not so loud seemed best.😊

Great video.. carried a 45 for 3 years.. never really liked it but that’s what our department had

you could convert your 45 to 460 rowland and use that , super and acp, if you visit aria ballistic engineering you will change your mind on 45.

At 8:06, what cartridge is this? He alluded to it being his favorite suppressed cartridge; I assume rifle.

Ballistics gel cant tell us which one hurts more

The US military also buys from the lowest bidder. Adapting 9mm, standardizing with allies, was a cost decision more than a technical decision.

A 9mm may fail to expand, but a .45 will never shrink

Everybody's Grandpa rolling in their graves over their kids simping for Kraut rounds. 😂

Thank you, Ray Romano.

It started raining because Thor heard you badmouthing his hammer.

The military went with 9mm in order to have a common cartridge with our NATO partners. Some special operations groups still use it.

I agree with everything single thing you said but for some reason I still love 45 acp

The U S Army was using the 1911 into the 90s that I know for a fact, because i carried one.

BUT ITS GOD'S CALIBER!

I can hear my great grandpa and great uncles arguing about whats better 45acp or 357 magnum on the back porch in NC right now.

As far as I know, the FBI Hostage Rescue Team still use a Springfield 1911 in 45acp.

Carry what you want, the streets don't care about popularity or capacity. It's self defense, what can you use to defend yourself/family with? What can't you shoot proficiently and accurately?

"John Browning is smiling on me Imperial. Can you say the same?" -Some dude in Skyrim

ALL CALIBERS MATTER!!!

Consider the rain a warning. Next time it'll be THUNDER and LIGHTING!

Your hog silhouette example is exactly why and where the term "knockdown/stopping power" comes into play ;)

“Two World Wars!”

Let’s see, wasn’t the 45 acp adopted to defend against Moros where 38 special wouldn’t do the job. So what changed? The 45 acp issued hardball ammo. Now we have hollow point ammo. I learned to shoot with 38 special then 357 magnum. The recoil of the .357 was a lot more than I wanted. The 45 acp to me is easier for me to control and I’m pretty proficient with it. YOU carry what you want. I’LL carry what I want. Besides even if the Hollow point clogs and doesn’t expand at least I have the same 230 grain round as the original was designed for

They tested 45acp on cows. And I live in a state that has more cows then humans. I know who the real enemy is and what I'm carrying.

Any firearm can be effective so long as you can hit what you aim at. I still prefer the .45. I love the sound, the feel, the hard hitting power of a properly expanding hollowpoint. Years ago I watched a program that was put on by U.S. military vets talking the pros and cons of the 9mm and .45 acp. This was after the first Gulf War. Because of the rules of warfare concerning types of firearm ammunitions I observed a majority of cqb specialists complain that their 9mm was inadequate to useless in a cqb situation. They claimed that if their opponents managed to force a close quarters battle there were far too many instance where when a soldier was forced to rely on just their 9mm sidearm the weapon would/could not stop an adrenalized attacker. They'd just keep coming even after multiple hits, but the soldiers with .45 acp were not having as many issues with that. They were claiming that a .45 acp would smash their opponents back and actually stop the threat. So many soldiers were sending home for 1911's and other .45 acp sidearms and fmj ammo because the military wasn't issueing them in any quantity in the field any longer. That was what made me choose the .45 acp. Especially since I am not restricted in what type of ammo I can use. I watched ballistics testing for several bullet types in both calibers. I made my final decision based on that. I'm keeping my .45 but I'm not dissing what others choose to carry. In the end it's whether or not the user can effectively put rounds on target and what they feel comfortable with using.

I'm pretty sure the US military is still using .45 because the marines have those .45 caliber pistols still.

I think it’s funny how people think that they can dodge a projectile because it’s “only going 830 fps.” 😂

You missed a big pro. Living in a state where magazine capacity is restricted to 10 rounds, one would want to get the most bang for the buck in their carry weapon.

Standard sidearm when I was in the military, I loved it 45acp any day

When I was a kid, we had many veterans of WWII and Korea, and I talked to them often. They had real-world experience using the 45 ACP and swore by it because it was the only pistole to drop an adversary in one shot. I remember a conversation between 2 WWII veterans, one of which found a German 9mm Luger and used it in battle; he stated that he shot a German 6 times with the 9mm and still wound up in hand-to hand combat with him. He never used that 9mm again. Their logic, a big wallop from a slow bullet taring and punching its way through a human, causing massive damage, and that was with FMJ! They used it in actual battle against real humans, not ballistic jell or a statistics chart. I still like my 45 better.

Need to worry about the 9mm not expanding..........45 will not shrink.

The unconfirmed by the Japanese Navy, a 45 was used to shoot down a freaking plane.

I have been a fan of .45acp for a long time. Recoil is not much of an issue for me. 6'3", 300lbs. I'll admit I did buy a 9mm to carry as a backup, but I haven't had it long enough or trained with it enough to be my main sidearm. But it's small and light. Although, I do have an S.A. XD-S in .45acp, that works for now...

40 is the correct answer vs human sized questions

Love my 45 and trust it. No hate on 9 or any other caliber, carry what you know and trust. Good comedy video, thanks.

0:06 BLASPHEMY

You didn’t mention it was designed for stopping power…one shot stop!

A 9mm hollow point may or may not expand, but a .45ACP will NEVER shrink!

A 9mm may expand, but a .45 will never shrink.

🤣🤣🤣 In real world experiences, I've seen what the 9mm can't do and what the .45 ACP can. I will never trust my life to 9mm. I'll stick with the better calibers.

There's a reason the lighter smaller calibers are so commonly carried. HOWEVER, there is also a reason .45ACPs & 12ga shottys are so commonly used as home defense vs their "smaller faster and lighter" counterparts. It's because when it comes to sheer stopping power (that includes both size of hole left & cavitation of flesh) you cannot beat the big boys. The 9mm is far too fast as are .223 or 5.56 resulting in the target being shot and NOT KNOWING IT (pass throughs). How do I know this? I've personally witnessed guys take a few 9mm and keep coming! I've never seen someone eat some .45acp and keep walking. The reason the military went to lighter rounds was precisely to allow for more ammo carried, NOT for round effectiveness. As awesome as the .223/5.56 is neither will do the damage of a 30-06 or .308. I'm not crapping on 9s either. My daily carry is a double stack 9mm. Just like the video shows, you can carry a far smaller piece with 2-3x the ammo. But when it comes to my home.... the big dogs will be barking, not the smaller daily puppies.

The US military switched to 9mm to be compatible with European/NATO standards. Let's not pretend there was _any_ other actual reason.

Simple physics..the bigger the hole..the more juice fall out

its always stated the military dumped the 1911 in 1985, but i still carried one when i got out in '95.

Dig your show. But there's a reason the military adopted the .45 cal. It originally replaced the .38, cuz the .45 was better at putting down machete wielding fanatics who were often on drugs in The Philippines.

First they told me I don't need a .45, then they told me I don't need an AR, then they told me I don't need 30 rounds. Why are we telling people what they don't need?

Great content! For the purposes of home defense and carry, I use 45jhp, because I don’t want penetration, I want the threat to get knocked down and the projectile to stay in the threat.

When the US Army went to John Moses Browning and asked him to design a new caliber to replace .38, one of the requirements was for the round to stop a cow with 1 shot. 2 world wars and just about every campaign since is a great argument. Cow stopping power is what won me over though.

There is another factor that the 45 auto has an advantage over the 10mm and 9mm and that is for people who hand load ammunition . The different types of gunpowder that can be used in the 45 auto are impressive, both handgun and shotgun powder can be used and the fact that one can use unjacketed lead with the 45 auto is a big plus, It is inexpensive and very effective. Also because of the lower pressures the cases tend to last longer. Sometime you might try a test with a 45 lead 200gr semi wadcutter load in ballistic gelatin. I think you will be very surprised with its performance .( I know not to use handloaded ammunition in selfdefence firearm at this time )

80 years ago, when men had higher testosterone. Now they prefer 9 and 380😢higher soy diets

I carry a .45 and a 9mm. so.. not worried

I bought an FN 545 T for the sole purpose of suppressing it for fun and not defensive shooting. Don’t plan on buying a 10mm (although my cousin bought an XDM10 the day I bought my 45) or any other pistol calibers for that matter. I carry 9mm so the debate between the two is pointless to me as each has a completely different use case.

The 45acp was developed for close quarters military action. It was designed to impart a knockdown to your adversary. The lower velocity and large projectile ensured that the bullet would stop in the body with a solid torso hit thereby imparting all the rounds energy to the target (one shot stop). Bullets that pass through the body regardless of muzzle energy do not impart all that energy to the target. Winners of 9mm gun battles are often decided by who quit breathing first. You may get more rounds in a 9mm mag but you will need them. The 10mm is a valid caliber with good performance. If carrying for bear the 10mm with underwood ammo is a good choice. For personal defense I carry 45acp. I have a couple modern pocket 9mms that I put in my pocket at gas stations and convenience stores. I carry a 44mag in the forest where I live for bear defense. I would be very slow to dismiss a battle proven cartridge designed by a true genius John Moses Browning!

I have a modest collection of 1911 all STEEL most in 45 acp. Not a lite weight Tupperware gun. I occasionally carry one and only use #UNDERWOOD_Ammo for self defense. Try that and get back to me.

One of the DUMBEST videos I have ever seen regarding handguns. I'll take a Colt 1911 .45ACP loaded with 185 grain HP ammo any day over any OTHER semi-auto handgun ANY DAY OF THE WEEK.

Depends on the state, mag restrictions, cost and use. 1) Restrictions. In CA for example you cant currently purchase mags that carry more than 10 rds. 2) If used for carry or home defense you prefer a round that doesnt over penetrate but can still deliver A LOT of punch. 45 acp has a reputation for hitting hard. 3) Availability. Nuff said. 10mm ive seen out of stock way more than 9mm and 45acp and doesnt always exist in bulk at my local gun stores and big box stores. 4) Cost. 45acp costs around 45c-50c per round for target rounds. 10mm is around 60c-75c per round. 9mm is 25c a round. 5) The view on the second amendment by local officials. The story of Harold Fish should be a good example. The prosecutor basically played up the fact that he had/used a much more powerful 10mm versus 9mm. 6) Lastly use what you have or is available to you and you can train with. I highly recommend people watch Paul Harrell's videos Personal Protection: 10mm vs .45 ACP and Paul's Top 5 Tips for Surviving a Self Defense Shooting. There is a ton of wisdom there. With those first 3 reasons alone i prefer 45acp for home defense. 45acp fmj doesnt penetrate a whole lot and with hollow points you can expect very little over penetration. For carry im not 100% sure though i would be ok carrying either 45acp or 9mm.

Real gun guys don’t come up with a reason to not get a gun.

I like both cartridges, but the problem with using muzzle energy is the basic formula itself. KE = 1/2 of MV 2. It heavily favors muzzle velocity, so a bullet moving faster has a bigger advantage. If one was to use the Taylor Knockout formula by John Pondro Taylor the 9mm has a KO score of 7 and the .45 goes to 14 both using Hornady Critical Duty loads. I am not saying muzzle energy or KO score is a perfect way to determine effectiveness, basically both are paper ballistics. What I do know is just about any handgun is underpowered for the task at hand, stopping the human predator animal. Shot placement is key. For me, I shoot 9mm better. Also, weight most 9mm today can be had in small light weight packages. But I am not about to throw out my .45's

10mm, .40, then .45. All three work as designed and my order of choice. And i dont feel under gunned with my Colt Commander in .45 acp.

Sorry, I'm keeping my .45. I much prefer it to my 9mm. I'm watching these so-called "tests" that fairly obvious that, because the announcer is so biased against the .45. gins the test to make it look worse. Bud, if you don't like a .45, don't use or buy one. I will give you the capacity issue, no lie there. What is not being mentioned is the main reason the U.S. military went to the 9mm was because it was what our NATO allies were using. Recoil? Depends on the ammo and pistol. A S&W M&P 2.0 with a ported barrel doesn't have as much recoil as my 9mm.

It's your channel, your opinion. You presented your perspective. I'll keep my 45 ACP all day, every day, thank you very much.

The main reason the U S ditched the .45 was to comply with NATO ammo compatibility guidelines.

"Velocity and expansion are variables! Mass and cross section are absolutes" Col Cooper