understanding 357 380 and 38 special


desert gator
March 19, 2009, 11:36 PM
ok this thread has a few questions.
1. Is a .380 and 38 special the same round?
2. I hear that a .380 can shoot a .357 also is that true? If so does it just go one way or both ways?
3. Is a .357 considered a more powerful round than a .380 or 9mm?

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March 19, 2009, 11:44 PM
1. No. .380 is an auto caliber and is rimless. Also known as 9mm Kurz or .380 Colt (ACP). .38 Special is a rimmed revolver round.

2. No. A .357 revolver will also shoot the shorter and lower pressure .38 Special. But a .38 Special revolver will not shoot the longer and more powerful .357 Magnum.


desert gator
March 19, 2009, 11:49 PM
thank you vonderek, this brings up a new question what is a rim? If some bullets are rimmed and some rimless?

March 20, 2009, 12:00 AM
If some bullets are rimmed and some rimless?Some calibers are rimmed and some calibers are rimless.

Revolver calibers are 99% rimmed. The rim is used to headspace the cartridge, keeping the round from falling to far into the chamber (cylinder).

99% of auto calibers are rimless. Those rounds headspace on the case mouth. It stops the round from going too far into the chamber.

March 20, 2009, 12:04 AM
Cartridge Specifications at Handloads.Com (http://www.handloads.com/articles/cartridge.htm)

March 20, 2009, 12:05 AM
A loaded cartridge consists of:

* the case, usually brass, can be aluminum or steel
* The bullet
* poweder
* Primer

THe loading procedure is to size the case in a press to make sure
it is the correct size for the chamber.
then the primer is pressed into the brass case.
next step the powder charge is placed in the primed case
THen the bullet is pressed and 'Crimped" into the mouth of
the case - The crimping makes the case mouth hold the bullet
secure. It is important bullets are securely crimped.

Now, at the rear of the case a 'rimmed' case has a base that is
a greater diameter than the diameter of the length of the case. This
rim allows the extractor in the gun to hook onto it so it can be removed
mechanically. the Semi-auto cartridge is called rimless but it really does
have a rim but the rim is the same diameter as the case. The 'rimless' case
is used in semi-autos because the cartridges are contained in the
stacked magazine and a rim might allow two cartriges to catch rims on
each other - called 'rimlock.' The Rimmed cartrdges are used in Revovlers
so to get them out of the cylinder a rod runs through the cylinder with a
'star' of 'u's that can get a grip on the rim of the cartrdges and 'extract' them.

hope this helps.... anybody got a link to some basics?


desert gator
March 20, 2009, 12:05 AM
thanks walkalong and randall I thought that that might be the diff. Its cool to learn new stuff, now I know that a 38 is a revolver round and 380 is an auto round. What about a 38 super? Is that the same as 380?

March 20, 2009, 12:09 AM
.38 Super (http://www.handloads.com/articles/cartridge.htm) is quite a bit longer and more powerful. Sort of like the .357 (http://www.handloads.com/articles/cartridge.htm) to the .38 Spl. (http://www.handloads.com/articles/cartridge.htm), sort of. It is a semi rimmed case, by the way. The .380 (http://www.handloads.com/articles/cartridge.htm) is rimless, like the 9X19 (http://www.handloads.com/articles/cartridge.htm) (AKA 9MM)

anybody got a link to some basics?Post #5

March 20, 2009, 12:25 AM
Desert Gator, many on this list like Walk Along refer to specific cartridges as "Caliber's this is incorrect use of nomenclature.

Each cartridge has a number of unique characteristics, caliber being one of them.

The Calilber only refers to the bore - the inner diameter of the barrel. to the rear of the bore is the chamber which contains the case of the cartrdige, the bullet is resting at the entrance to the bore in a semi-auto. In a revolver it sits in the front of the cylinder. so,

.38 Special = .357 Diameter bullets
.357 Magnum = .357 diameter bullets but the case is 1/8" longer
.380 Auto/ACP = .355 diia.
9mm luger was first called the
9mm parabellum = .355 dia.
.38 SUper = .355 diameter and the rebated rim that Walkalong called it means the rim is actually slightly smaller in diameter than the cartrdige case .

cartrdges created in the year:
.38 Special 1899
.38 ACP/Auto 1902
they're low pressure because this was when smokeless powder was first
being used pressure ranges are in the 18000 PSI generally

Higher pressure = 35000 or higher and thse include the
other three 9mm luger, 1902, .38 SUper 1929 and the
.357 Magnum 1935.

So, you see cartrdiges can have the same calilber, but the shape or
lenth of the case is different but some have the same caliber.



9mm Luger


March 20, 2009, 12:30 AM
Desert Gator, many on this list like Walk Along refer to specific cartridges as "Caliber's this is incorrect use of nomenclature.Technically correct. We loosely refer to the .357 caliber, or .38 caliber, but that is not really correct. Cartridge would be a better word.

desert gator
March 20, 2009, 12:31 AM
thanks randall that helps allot to clear things up.

March 20, 2009, 12:33 AM
Another n00b here.

Since this thread is in the Autoloaders section, am I correct in noting that most autoloaders do not feed/shoot .357 Magnum rounds, but rather the shorter .357 Sig?

desert gator
March 20, 2009, 12:38 AM
Good question buck000 I looked in my gun guide and see autoloaders that shoot .357 sig, but none that shoot the .357 magnum.

March 20, 2009, 12:55 AM
Ok, noobs, the history of cartridge development is long story.... but briefly if a cartridge has a name associated with a certain company you can
bet they created it.

The .357 Magnum - only Semi-Auto I can think of was the Coonan but the cartridge is so long it made a semi-auto that looked like a 1911 but due to it's length in the grip area you had to have big hands to use it well. It also had problems - so it faded away about 25+ years ago.

.357 Sig is a rimless case that is based on the .40 S&W cartrdige the neck is pressed to a shape called the bottleneck, down to to accept .355 diamter bullets. SIg named it .357 I guess because it sounds more powerfull
and is a common name for the mag.?

FYI - the correct full name for the .38 Special is
.38 Smith & Wesson Special

FYI - the 380 AUto was first called the .38 ACP -
ACP = AUtomatic Colt, Pistol.


March 20, 2009, 01:12 AM
The .38 ACP/.380 Auto in Europe with a metric designation is 9x17 meaning it's bullets are 9mm and the case is 17MM in length. It's low pressure and used in semi-autos that generally have a fixed barrel and a
strong recoil spring to handle the action of the slide in recoi, and to return
the slide forward. It originated in about 1902 by the designer John M
Browning. He then designed the 1905 Colt in .45 ACP, and improved it in the
smei-auto we know now popularly as the 1911. THe 1911 is a delayed unlocking of the barrel via the rear liink and has a recoil spring, but it allows the 1911 to handle the more powerful .45 ACP cartridge. This design is used in the majority of semi-autos designed in the 20th century in basic concepts
- lots of variations on triggers, and other stuff.

so, a .38 ACP/.380 Auto has bullets .355 Diameter, which in metric is a 9mm. THe 9mm Luger is metric/euro design. 9x19 - longer case and a thicker base allows it more powder and used in the stronger actions can be fired at higher pressure so it has heavier bulllets and higher velocity.


desert gator
March 20, 2009, 01:24 AM
thanks for all the input blindjustice. I did not realize that caliber is the diameter of the barrel and not the diameter of a bullet.

March 20, 2009, 01:53 AM
The Barrel has a bore that has a diameter matched to the diamter of the bullet. The rifling imparts the spin on the bullet so when it leaves the muzzle
it has stability so the cylindrical shape doesn't tumble.

on a different note,

In Europe in the 20th century, the smaller .380 Auto pistols were used by
the police in many countries. In the USA with our long history of revolvers in taming the west, etc. the Double Action revolver in .38 SPecial was most popular with LEOs until the eventual changeover to semi-autos in the late 60s, and 1970s.

So, another note why in the heck you might ask is a .357 bullet fired out of the .38 S&W SPecial - well why is it called a .38? Well, Colt and Smith & Wesson devleoped the revolvers prior to the invention of the semi-auto pisol.
This goes back to balckpowder revolvers with the two most popular ccalibers
being .36 and .44 cap and ball. Colt patented the cased cartridge in 1873 with the old single Action Army along with the top strap to enclose the cyolinder. S&W had top break Double action revolvers and each came out with more powerful rounds. i.e. cartridges, Well S&W had a .38 S&W then
Colt just lengthened that case and coalled it the .38 Long COlt although it was still a ".36" or the inside DIameter of the chamber was .38 so when S&W created their first DA revolver they lengthened the .38 Long COlt by 1/8" and it is the cartrfidge known as the .38 S&W Special. In 1908, S&W lengthened the .44 Russian cartridge by a bit and voila it was named
the .44 Special.

The .357 Magnum was so named becauswe it was the first to use the slow buringing but much higher pressure smokeless powders.


March 20, 2009, 02:14 AM
oh, .38 Super - why is it called a .38 ?

Well, the cops wanted something with more power to penetrate varriers, namely cars, and they already had the .38 Special, Colt lengthened the
9mm luger cartridge to fit into the action of a 1911 - see a .45 ACP in metric is 11.43x 23 - so they named this new one the .38 Super for LEOS
and it was loaded pretty hot back then, today ammo companies load it down
to (mm luger velocities but if you reload the .38 SUper has more capacity to
have more velocity than a 9mm Luger. S&W responded by loadeing up the .38 Special ammo to .38 Special HIgh Velocity but it was only to be used in their big large N-frames then the .357 magnum was born in 1935.

The next big step forward in semi-auto ammo was the 10mm Auto, it came out of Sweden and Norma aamo company. THe .40 S&W is a shortened 10mm Auto to fit into semi-autos that are built length wise for the 9mm luger and smaller hand = for more average sized people.


March 20, 2009, 09:08 AM
The .357 Magnum - only Semi-Auto I can think of was the Coonan
Desert Eagle and LAR Grizzly (with a conversion kit)

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