9mm compared to .38 special

Status
Not open for further replies.

Dewey 68

Member
Joined
Apr 6, 2010
Messages
287
Location
Corrupt Illinois
I've noticed that when comparing similar loads between .38 special and 9mm, the 9mm will have higher velocities. I'm assuming this is due to the higher pressures for the 9mm. The .38 special was originally designed for black powder, which I'm also assuming is why the cartridge is so big, and the lower pressure is due to the extra space behind the bullet.

I just find it interesting that the 9mm cartridge is a higher pressure design compared to the .38 special and .45 acp designs, all of which were designed around the same time.

Was the 9mm always designed around smokeless gunpowder?
 
In the USA, in 1890, a patent for smokeless powder was obtained by Hudson Maxim.
If I understand correctly, in order for S&W to use it they would've had to pay Hudson a fee. So they developed the .38 spl based on the old black powder. As you surmised, hence the case size.

The 9mm Luger was developed in Germany, and again as you surmised was developed using the new fangled smokeless powder.
 
One thing, the .38 Special doesn't have low pressure because the case is big, it has low pressure because it's designed to have low pressure. The .357 Magnum case is even longer than the .38 Special yet it is loaded to more than twice the pressure of a .38 Special. (17,000 PSI compared to 35,000 PSI)
 
One thing, the .38 Special doesn't have low pressure because the case is big, it has low pressure because it's designed to have low pressure.

You can load up a .38 special case to .357 magnum velocities but you should only shoot them from a .357 magnum chambered gun. The .38 special guns are only designed for .38 special pressures.
 
.357 magnum will most likely be my next purchase

I've got the dies to do .38 special/.357 magnum, and a buddy of mine already has a .357 magnum, so I've been reading up on the design. Thanks for the information guys.
 
While the .38 Special was introduced with black powder, it was being sold with smokeless within a year or so. .38 pressures remain low because the companies are terrified that you will keep using an old gun without cylinder heat treatment or even worse, put them in a .38 Long Colt.
 
Traditionally, 9mm P-'08 Bullets were quite a bit lighter than the Bullets used in .38 Special.

Light Bullet in .38 Special allows higher FPS...Heavy Bullet in 9mm P-'08 requires slower FPS.

.38 Special was among the last 19th Century Revolver Cartridges to be developed.

9mm Luger, an early 20th Century Autoloading Cartridge.

I suppose technically, the .38 ACP was also a 19th Century Cartridge, since it was designed in 1898-1899, even if high Pressure ( relatively ) for Smokeless, and, of course, for an Automatic.

Cartridge development was and remains a somewhat wacky tale of variety and diversity.
 
You can load up a .38 special case to .357 magnum velocities but you should only shoot them from a .357 magnum chambered gun. The .38 special guns are only designed for .38 special pressures.
Do not construe this statement to think that you can use 357 Magnum load data if you are going to shoot them in a Magnum revolver!!!!

There are 2 things wrong here:
1. The smaller case will greatly increase pressure and this is dangerous even in revolvers designed for the magnum cartridge.

2. The 357 case was made longer on purpose to keep them from chambering in a 38 special revolver. Loading in the smaller case would allow such a mistake and would surely be disastrous.

Please be safe and make a 38 a 38 and not a magnum.

Bill
 
Do not construe this statement to think that you can use 357 Magnum load data if you are going to shoot them in a Magnum revolver!!!!

Okay, this is partially true. However, I have loaded up a bunch of .38 special cases to magnum powder charges and shot them just fine. If you do A LOT of research you can find loads for the .38 spcl that will give you magnum velocities. That said, almost nobody does it because of the crazy liability in the chance that someone will think that will be okay through a gun designed to shoot .38 spcl loads. If you are going to do it then the right powder choice is essential. Like my fellow Idahoan said, depending on the powder used the shorter case could cause excessive pressures. It is always better safe than sorry. I only did it last year because magnum brass was litterally impossible to come by. In many ways it still is. Look up the history of the .357 magnum to see where it came from if you still have any doubts.
 
Last edited:
heres a little exerpt with load data for the .38/44 loads. This was a load used by Elmer Keith in the development of the .357 magnum.

Caliber Bullet type Weight Powder Weight Velocity
38 Special +P+ * LSWC 158 grains 2400 13.5 grains 1325 FPS

Just a short word of caution: MAXIMUM loads! If you choose to load any of these start low and work up gradually. We do not need to give the anti-gunners any ammunition by blowing ourselves up. Since I have no control over your loading practices I take no responsibility for your safety. These loads were assembled with Winchester primers and brass and hard cast bullets.

*This 38 special load should be consider a top end 357 Magnum load and should never be fired in anything other than a 357 magnum. Todays 2400 powder is faster burning than it was in the 1930's when Elmer Keith worked up this load. Many people feel that this should be reduced to 12.0 gr with modern 2400 powder.
 
It has been [strike]argued[/strike] discussed many times here whether it is a good idea, or not, to load .38 cases to over .38 pressures. I am in the camp to not do it simply for the chance someone besides myself would get hold of them and use them in a .38 Spl revolver. A competent & careful reloader can do it and stay safe, but the potential is there.

Jake is right, .357 brass has been scarce for a while now, and over priced when it was found, while .38 brass has been plentiful.

There are revolvers out there, such as the .38/44 Smith, that can handle a lot more than standard .38 rounds, but there are also revolvers out there where +P .38 isn't a good idea.

The old timers loaded many a .38 Spl hot until .357 Mag revolvers answered their prayers.
 
You can load .38 special cases and make .357 mags out of them, provided the bullets you use are long enough and use them in a revolver chambered for .357 mag. Currently I am loading for plate league but didn't want to change over my Dillon, as it is setup for .38 special, which I use constantly for Cowboy Action loads. I wanted to use a .158 gr. RNL .357 mag. for plates but use .125 gr. TC .38 specials for Cowboy loads, so the best way I could do this without changing very little was to use .38 special cases, and just seat the bullet to a depth that matches the OAL of the same bullet loaded in a .357 mag. case. Doing this allows me to only adjust my seating die and leave the rest alone. Works for me, LM.
 
Last edited:
Status
Not open for further replies.
Back
Top