Blue Steel
New member
There is a reason that .380 ACP is also called 9mm Kurz (short) and 9x17mm.
Caliber Question
- Thread starter StiveC2007
- Start date
So let's say we have two guys. BillyBob and BillyRay. BillyBob has a 34" waist, is 5'9" and weighs 180 lbs. BillyRay on the other hand is 6'3" and tips the scales at 215 lbs. BillyRay also has a 34" waist.
Are these guys the same size?
This is very much what you are trying to argue. Fact is, the 9mm uses a heavier bullet of the same diameter. Because it is heavier yet the diameter is the same, that weight is made up by it's length. So it's not the same, it's bigger. And that bullet moves at a similar speed, and typically faster. And the cartridge itself runs a pressure that is 50% higher or more. Heavier bullet going the same speed or faster produces more energy.
.380 and 9mm are no more "the same" than is a .45 auto and a .45-70 Govt.
.380 acp v 9mm parabellum (copied from the wikipedia):
.380 acp
Case type Rimless, straight
Bullet diameter 0.355 in (9.0 mm)
Neck diameter 0.373 in (9.5 mm)
Base diameter 0.374 in (9.5 mm)
Rim diameter 0.374 in (9.5 mm)
Rim thickness 0.045 in (1.1 mm)
Case length 0.68 in (17.3 mm)
Overall length 0.984 in (25.0 mm)
Max pressure 21,500 PSI
9mm
Case type Rimless, straight
Bullet diameter 0.356 in (9.03 mm)
Neck diameter 0.380 in (9.65 mm)
Base diameter 0.391 in (9.93 mm)
Rim diameter 0.392 in (9.96 mm)
Rim thickness 0.035 in (0.90 mm)
Case length 0.754 in (19.15 mm)
Overall length 1.169 in (29.69 mm)
Max pressure 35,000 PSI
So as you can see, some dimensions are the same and some are different.
Questions #2:
Yes you can shoot .38 special in .357 magnum revolvers; but not the reverse due to the greater pressure of the .357 and the longer case length..
.38 Special
Case type Rimmed, straight
Bullet diameter 0.357 in (9.1 mm)
Neck diameter 0.379 in (9.6 mm)
Base diameter 0.379 in (9.6 mm)
Rim diameter 0.44 in (11 mm)
Rim thickness 0.058 in (1.5 mm)
Case length 1.155 in (29.3 mm)
Overall length 1.55 in (39 mm)
Max pressure 17,000 PSI
.357 magnum
Case type Rimmed, straight
Bullet diameter 0.357 in (9.1 mm)
Neck diameter 0.379 in (9.6 mm)
Base diameter 0.379 in (9.6 mm)
Rim diameter 0.44 in (11.2 mm)
Rim thickness 0.06 in (1.5 mm)
Case length 1.29 in (33 mm)
Overall length 1.59 in (40 mm)
Max pressure 35,000 PSI
The Worm Can is Officially Open
The primary question has been well answered; with the possible exception of price tag, 9mm Luger, aka 9mm Parabellum, aka 9x19 NATO, aka "9" is the same size or larger in most any dimension of comparison.
However, it raises a larger question: What does 'caliber' mean?
Strictly (originally) speaking, 'caliber' means a measurement in .01 graduations. As in, ".25" is 25 caliber, or .25 inches. In the world of firearms and ammunition, it came to mean the measurement of bore diameter, as in .257, meaning 257 thousands of an inch. This was extended to metric measurement, as in 6.35 mm - the metric equivalent of .25 caliber. It has now been morphed into the term describing a particular cartridge; as .25 ACP or 6.35mm Browning.
Further confusing the issue is that .38 S&W, .38 Short Colt, .38 Special, Super .38 and several others are not .38 inches in diameter. They are for the most part, defined as being .358 inches in diameter. However, when manufacturing tolerances are considered - as they must be in the real world - the actual diameters range from .354 to .362 inches in diameter.
As Abber implied, the .460 S&W and the .45 Colt have the same bore diameter. The .300 Winchester Magnum has the same bore diameter as the .308 Winchester as the .300 Whisper. And those bore diameters are only .004 inches different than the bore diameter of the .32 ACP or .32 S&W Long cartridges.
For those who are interested in following the logic and lack of logic in the field of cartridge designations, I recommend Cartridge of the World, published by Gun Digest Books (www.gunlistonline.com). This work not only lists and describes most of the cartridges known in history around the world, it has historical and ballistic information. Most reloading manuals have a good deal of information on the subject as well.
The primary question has been well answered; with the possible exception of price tag, 9mm Luger, aka 9mm Parabellum, aka 9x19 NATO, aka "9" is the same size or larger in most any dimension of comparison.
However, it raises a larger question: What does 'caliber' mean?
Strictly (originally) speaking, 'caliber' means a measurement in .01 graduations. As in, ".25" is 25 caliber, or .25 inches. In the world of firearms and ammunition, it came to mean the measurement of bore diameter, as in .257, meaning 257 thousands of an inch. This was extended to metric measurement, as in 6.35 mm - the metric equivalent of .25 caliber. It has now been morphed into the term describing a particular cartridge; as .25 ACP or 6.35mm Browning.
Further confusing the issue is that .38 S&W, .38 Short Colt, .38 Special, Super .38 and several others are not .38 inches in diameter. They are for the most part, defined as being .358 inches in diameter. However, when manufacturing tolerances are considered - as they must be in the real world - the actual diameters range from .354 to .362 inches in diameter.
As Abber implied, the .460 S&W and the .45 Colt have the same bore diameter. The .300 Winchester Magnum has the same bore diameter as the .308 Winchester as the .300 Whisper. And those bore diameters are only .004 inches different than the bore diameter of the .32 ACP or .32 S&W Long cartridges.
For those who are interested in following the logic and lack of logic in the field of cartridge designations, I recommend Cartridge of the World, published by Gun Digest Books (www.gunlistonline.com). This work not only lists and describes most of the cartridges known in history around the world, it has historical and ballistic information. Most reloading manuals have a good deal of information on the subject as well.
If the .38 special's big brother is the .357 magnum, why isn't the .44 special's big brother called the .429 magnum? 
And why on earth did Winchester beef up the 38-55 into the .375win and put it in a shorter case that would fit in the low pressure guns??? I guess it's a good thing for some that the .375win has become obsolete.
And why on earth did Winchester beef up the 38-55 into the .375win and put it in a shorter case that would fit in the low pressure guns??? I guess it's a good thing for some that the .375win has become obsolete.
StiveC2007
New member
How could i be wrong sevens i told him that the 9mm and the .380 were the same size bullet now how could i be wrong when everyone on here says they are the same size bullet (.355)
Its a hold over from the black powder days...
The names of bore sizes, and many old cartridges. Early cartridges used "heel" type bulets , the same as the .22rimfire still does today. There is a heel of the bullet that fits inside the case, while the bulk of the bullet is outside the case, and has a section of the bullet the same diameter as the case. These bullets were lead, and were lubricated, often with a sticky lube that picked up dirt, lint, and other debris. This was less than optimum, and this problem was overcome with two solutions.
One was the developement of a dry, waxy lube (still used on .22s) and the change in bulet design to move the lubricated part inside the case. This meant a reduction in the diameter of the bullet.
The early, familiar names for bore sizes were kept, but the actual bullet diameter, was reduced.
ALso, the bullet diameter of the 9mm and .380 is the same, as many have noted. The names used by ammo makers to identfy a given cartridge may have a close relationship to some actual measurement of the bullet, or the case, or they may not.
The names of bore sizes, and many old cartridges. Early cartridges used "heel" type bulets , the same as the .22rimfire still does today. There is a heel of the bullet that fits inside the case, while the bulk of the bullet is outside the case, and has a section of the bullet the same diameter as the case. These bullets were lead, and were lubricated, often with a sticky lube that picked up dirt, lint, and other debris. This was less than optimum, and this problem was overcome with two solutions.
One was the developement of a dry, waxy lube (still used on .22s) and the change in bulet design to move the lubricated part inside the case. This meant a reduction in the diameter of the bullet.
The early, familiar names for bore sizes were kept, but the actual bullet diameter, was reduced.
ALso, the bullet diameter of the 9mm and .380 is the same, as many have noted. The names used by ammo makers to identfy a given cartridge may have a close relationship to some actual measurement of the bullet, or the case, or they may not.
scottaschultz said (of the .38 and .357)
"This may be nit-picky, but I would replace the word hangun with revolver since those two type of ammunition are specifically for a revolver, not a pistol.
Scott"
Well, so long as we are being nit-picky...
This was a true statement many decades ago. The .38special and the .357 magnum were designed for revolvers, and their rimmed cartridges made them difficult to adapt to semiauto magazines. However, just to name a few pistols that made such adaptations:
S&W Model 52, debuted 1961, firing .38special (wadcutter only)
Coonan .357 magnum 1980s-1998, .38+P conversion kits available; in their last year of operation, they were supposedly bringing out a .41 magnum version but went out of business before it became available.
Desert Eagle .357 magnum, patented 1983, US debut 1985 (note, this pistol later came out in .41 magnum - since discontinued - and .44 magnum calibers)
LAR Grizzly was also available in .357 magnum and .44 magnum, plus several other calibers.
Still picking nits, don't forget single-shot handguns, such as the Thompson/Center Contender series. You can still get those in .357 magnum and .44 magnum.
If we really wanted to reach, there are several rifles and carbines that chamber the .357/.38 and the .44
Cheers,
M
"This may be nit-picky, but I would replace the word hangun with revolver since those two type of ammunition are specifically for a revolver, not a pistol.
Scott"
Well, so long as we are being nit-picky...
This was a true statement many decades ago. The .38special and the .357 magnum were designed for revolvers, and their rimmed cartridges made them difficult to adapt to semiauto magazines. However, just to name a few pistols that made such adaptations:
S&W Model 52, debuted 1961, firing .38special (wadcutter only)
Coonan .357 magnum 1980s-1998, .38+P conversion kits available; in their last year of operation, they were supposedly bringing out a .41 magnum version but went out of business before it became available.
Desert Eagle .357 magnum, patented 1983, US debut 1985 (note, this pistol later came out in .41 magnum - since discontinued - and .44 magnum calibers)
LAR Grizzly was also available in .357 magnum and .44 magnum, plus several other calibers.
Still picking nits, don't forget single-shot handguns, such as the Thompson/Center Contender series. You can still get those in .357 magnum and .44 magnum.
If we really wanted to reach, there are several rifles and carbines that chamber the .357/.38 and the .44
Cheers,
M
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It depends on how you define "bigger". I'd say the .380 bullet is smaller than the 9mm bullet. They have the same diameter, but .380 bullets are in the 90-100 grain range while 9mm bullets will typically weigh in between 115 and 147 grains.
Isn't a 6" #2 Phillips screwdriver bigger than a 4" #2 Phillips screwdriver?
imthegrumpyone
New member
Bigger is not always better.
imthegrumpyone
New member
Bigger is not always better. As far as size ! nothing's the same size, vary confusing isn't it ?
As far as size ! nothing's the same size, vary confusing isn't it ?Seriously, man, they are the same diameter bullet. They are not the same size.
A round log on the fire and a telephone pole. Same diameter, NOT the same size.
If you want to point out how much the other guy doesn't know, you've done that. If you want to be right, you missed. Sorry.
9x19 Luger, 9x21, 9mm Largo, .380 ACP, .38 ACP, .38 Super Automatic, .357 Sig, .356 TSW, and 9x23 Winchester all use the same .355-.356 diameter bullets although case dimensions, bullet weights, pressure specifications, and velocities vary. Standard .380 ammunition is a straight-walled case 17mm long with a 95grn FMJ bullet while standard 9mm is a slightly tapered case 19mm long with a 115grn FMJ bullet.
9x18 Makarov uses a larger .362 diameter bullet, but the weight is similar to .380 ACP and the velocity and energy are less than 9x19 Luger.
.38 Long Colt, .38 Special, .357 Magnum, .357 Maximum, and .357/44 Bain and Davis all use the same .357-.358 diameter bullets although case dimensions, bullet weights, pressure specifications and velocities vary from cartridge to cartridge.
Both .38 Long Colt can be fired in a revolver chambered in .38 Special, both can be fired in a revolver chambered in .357 Magnum, and all three can be fired in a revolver chambered in .357 Maximum, but .38 Special can't be fired in revolvers chambered for .38 Long Colt, .357 Magnum cannot be fired in revolvers chambered for .38 Special or .38 Long Colt, and .357 Maximum cannot be fired in anything but a .357 Maximum chambered revolver.
.38 S&W and .38/200 British use a larger .361 diameter bullets but are far less powerful than .38 Special, .357 Magnum, .357 Maximum, or .357/44 B&D.
9x18 Makarov uses a larger .362 diameter bullet, but the weight is similar to .380 ACP and the velocity and energy are less than 9x19 Luger.
.38 Long Colt, .38 Special, .357 Magnum, .357 Maximum, and .357/44 Bain and Davis all use the same .357-.358 diameter bullets although case dimensions, bullet weights, pressure specifications and velocities vary from cartridge to cartridge.
Both .38 Long Colt can be fired in a revolver chambered in .38 Special, both can be fired in a revolver chambered in .357 Magnum, and all three can be fired in a revolver chambered in .357 Maximum, but .38 Special can't be fired in revolvers chambered for .38 Long Colt, .357 Magnum cannot be fired in revolvers chambered for .38 Special or .38 Long Colt, and .357 Maximum cannot be fired in anything but a .357 Maximum chambered revolver.
.38 S&W and .38/200 British use a larger .361 diameter bullets but are far less powerful than .38 Special, .357 Magnum, .357 Maximum, or .357/44 B&D.
Brian Pfleuger
Moderator Emeritus
Unless of course in the context of the conversation "size" meant diameter, which is almost certainly the case. It can be problematic to tell other people what they meant when they used a word.
At it's absolute basis, he wanted to point out that his buddy is wrong and he's done that. If that were all he wanted to accomplish, he's nailed it.
Problem is, he's not right either, no matter how you slice it. You can qualify it in any English you can muster, but from his original post his words are, "I kept telling him they were the same."
They aren't the same. You can't stick a 9mm in a .380 pistol and get the slide closed. You can stick a .380 in a 9mm pistol but it either won't fire (when it falls too deep) or it won't eject (when it can't stay under the extractor) or it'll split/rupture (because the chamber is too large) or any other problems.
Thus they are not the same.
A .25 acp and a .44 Magnum, they are the same, right? No, not diameter. Color! So they are the same, right?
No. They are not the same. No matter how you try to qualify it. .25 acp and .44 Mag are not the same. Niether then is .380 and 9mm, no matter what the diameter is. They are not the same.
I've never been a leading cause of a thread getting closed here on TFL, so this may be my first. It's getting away from discussing firearms and ammo and shooting. It's getting ridiculous. No matter what else gets said, when the thread gets closed or any warning PMs I get from an annoyed moderator, there's nobody here on TFL that is going to convince me to agree that the original poster is right when he says, "they are the same!" Dude is wrong, they aren't the same. His buddy thinks .380 is bigger, so he's even MORE wrong.
Problem is, he's not right either, no matter how you slice it. You can qualify it in any English you can muster, but from his original post his words are, "I kept telling him they were the same."
They aren't the same. You can't stick a 9mm in a .380 pistol and get the slide closed. You can stick a .380 in a 9mm pistol but it either won't fire (when it falls too deep) or it won't eject (when it can't stay under the extractor) or it'll split/rupture (because the chamber is too large) or any other problems.
Thus they are not the same.
A .25 acp and a .44 Magnum, they are the same, right? No, not diameter. Color! So they are the same, right?
No. They are not the same. No matter how you try to qualify it. .25 acp and .44 Mag are not the same. Niether then is .380 and 9mm, no matter what the diameter is. They are not the same.
I've never been a leading cause of a thread getting closed here on TFL, so this may be my first. It's getting away from discussing firearms and ammo and shooting. It's getting ridiculous. No matter what else gets said, when the thread gets closed or any warning PMs I get from an annoyed moderator, there's nobody here on TFL that is going to convince me to agree that the original poster is right when he says, "they are the same!" Dude is wrong, they aren't the same. His buddy thinks .380 is bigger, so he's even MORE wrong.
This whole topic causes much confusion for people new to the topic of firearms and ammunition. One would think cartridge designations would all be very precise, but that is often not the case. Some are designated by the barrel's bore diameter while others are by the bullet's diameter. Much of it is marketing hype; sometimes the company who developed the cartridge may want to use a number the shooting public is already familiar with, or they may want to make it sound exotic. It's mostly related to marketing and it can be confusing to the new shooter. Best source of info is a good reloading manual, even if you don't reload. It will give you precise measurements and often the history of the cartridge. You can get one for the cost of a box or two of ammo; the knowledge gained is amazing.
skydiver3346
New member
Ditto on what Mello2u said:
Pretty much sums it up. However, if I were you I would take both a 9mm and a .380 cartridge to your friend and place them side by side (like in the picture above). Seeing is believing and that should settle the argument once and for all.
Pretty much sums it up. However, if I were you I would take both a 9mm and a .380 cartridge to your friend and place them side by side (like in the picture above). Seeing is believing and that should settle the argument once and for all.