9mm vs. 38 Special

[TeamPrecisionIT]

This isn't really a caliber war, more of a need for an explanation. I have a 9mm pistol and a .38 Special revolver and I was shooting them both at the range yesterday and made an observation. I noticed that the .38 Special cases were significantly longer, maybe just a little less wide but according to the data, the .38 loses quite a bit on power and speed. How is that possible when there is much more room for powder in the .38 case against the 9mm? Maybe some of you guys that have been around longer can help me to understand this a little better.

Damian

 

[gmhamilton3]

Short version.
SAAMI pressure ratings for the 9mm are 35,000 PSI for standard and 38,500 for +P. There are no designated SAAMI specs for +P+ that I can find.
The .38 Special, SAAMI pressure for the standard pressure load is 17000 PSI. The +P has a ceiling of 20000 PSI. There are no SAAMI specifications for +P+, but there are some +P+ rounds available in this caliber. 356 to 0.358".
Long version.
http://www.hipowersandhandguns.com/9mm vs 38 Special.htm

 

[TheVirginian]

This was just covered in another thread. The thread title or specific forum section escapes me. Basically, the 9mm round develops higher pressure, so it's more powerful for its size. It isn't terribly more powerful in the long run however as velocity at muzzle and a short distance will show. since the bullet diameters are the same size, bullet weights can also be the same and again, that makes them pretty equivalent in terms of its ballistic effects on a target. The 9mm is actually a bit hotter as the gmhamilton3 states but it isn't enough to warrant any switch from one round to the other in search of ballistics performance.

The reason the 9mm is short is obviously for fitting more easily into an auto loading magazine. The reason that it is more popular is due to those auto loader magazines having a high capacity.
-Bill

 

[Marlin 45 carbine]

I've shot enough 124gr 9mm+P and 125gr .357mag into wood target mountings to know I don't care to suffer a 'hit' from either one.

 

[ArchAngelCD]

Along with the other correct information above there is more. The .38 Special case is so long because it was originally designed to be loaded with Black Powder. You needed the length to hold enough powder to achieve the desired velocity. When the caliber changed over to smokeless powder it left a lot of the case capacity empty because if you filled it with powder you would easily exceed the pressure ratings, especially for the guns of the time. The 9mm case is so small and the pressures are so high because it was developed for smokeless powder, not black powder.

 

[gmhamilton3]

In addition, the 9mm uses a "hotter" powder primarily to generate high pressures in a 4'' barrels. The .38 just cannot match this performance especially in a 2'' snubby. However performance is relative, both will kill you just as dead. Like you I have both along with a .45 and needless to say all 3 will be around for the next hundred years and for good reason.

 

[BlindJustice]

In the later part of the 19th century before the invention of smokeless powder which generates much more pressure per volume than
black powder the way ammunition makers made more powerful
CARTRIDGES ( a characteristic of aANY cartridge is it's Caliber which most
people use as a term to refer to specific cartrdiges FWIW ) was
to make the cartridges case length longer given the same calber as
it's predecessor. So when Smith & Wesson created the .38 S&W
SPecial cartridge it was a lengthened .38 Long Colt Cartridge HOwever,
the .38 Special as we refer to the cartrdge in a shorened name, was
created in 1899 and the blackpowder charge was 21.5 grains. By
1902, the BP charge was replaced with a lesser amount of smokeless
powder so the original revolver used the same cartrdige in order to not
have to redesn for a shorter new cartridge specifically desgned for
smokeless powder.

Several cartridges can share the same calilber but each cartridge has
a unique case hspae/dimensions.

Randall

 

[Brian Williams]

If you take a 38 Spec case and trim it to the same case capacity as a 9mm you will have the same basic round. In order to make sure you have the same internal capacity, you must fill a 9mm case to the mouth with water and measure that and then shorten a 38 case to whatever length that will hold the same amount of fluid. A 38 case might have a different web thickness or what ever and it might end up as a 9mmx20R instead of a 9mmx19.

I have often thought a 38S&W loaded to it's full potential with today's powders and projectiles in a revolver made with today's materials would be a great combination.

 

[doubs43]

Skeeter Skelton wrote that when he finally was able to lay his hands on a .357 Magnum revolver, he had trouble finding brass but had all the free .38 Special cases he could ever use.

Lyman made (still does) a mold (#358156) for a 158 grain gas-check bullet designed by a man named Ray Thompson. It has two crimping grooves. Loaded with 13.5 grains of 2400 in a .38 Special case and crimped in the lower groove, velocities in the 1200 fps range are achieved in a .357 Magnum revolver. This is a load that Skeeter used a lot and was completely satisfied with.

The above load makes use of the case capacity of the .38 Special to get a velocity close to that of a .357 Magnum. I've used it in a S&W 586 and it's very good in my experience.

CAUTION: DO NOT use this load in a revolver designed for .38 Special only. It's too hot for any revolver that isn't designed for .357 Magnum loads.

 

[Deanimator]

1. .38 Special was designed for black powder and early, less efficient smokeless powders which needed more case capacity.

2. .38 Special is MUCH better with heavier bullets. The heaviest commonly found bullet for the 9x19mm is 147gr. The STANDARD bullet weight for the .38 Special is 158gr., and at one time 200gr. was quite common. I simply don't like light bullets. I won't carry anything but 147gr. bullets in my 9x19mms. I won't carry anything lighter than 158gr. bullets in my .38s and .357s, and always some variation of the 158gr. LSWC-HP "FBI" load.

 

[BlindJustice]

Along the lines of comparing a case built for smokeless powder like the 9mm Parabellum (DOB 1908?) versus the .38 S&W Special (DOB 1899 BP/1902 Smokelss powder changeover ), I'd like to present the .45 ACP ( DOB 1905 )
and it's younger 'brother' the .45 Auto Rim ( DOB 1920) Even though the
.45 Auto RIm was designed for smokeless powder SAAMI keeps it rated at 14,000 PSI same as cartridges that started off designed for BP, like the .45 Colt, .44-40, .38-40, and even the .44 Special. Just what weak guns was the .45 Auto RIm ever chamberd for? Or was it balloon style brass which is
weaker ? WHen did ammo companies stop using the older Balloon style brass?

Rant on...

I've read of several handloaders who put charges of 12-13 grains of
#2400 in .45 AR to giddyup heavy SWCs, and Buffalo Bore just introduced a new loading for .45 AR. a 200 gr. SWC @ 1200 FPS. I've re-adjusted my
thoughts of my custom loaded leadhead 200 gr. SWC @ 1,025 FPS as certainly non +P in .45 ACP, as well as .45 AR for my 625. Heck the .45 AR has an extra thick rim, it's approx. 0.0910" thick for the correct spacing for
the firing pin, a .45 Colt for instance has a rim approx. 0.0615" thick. So, the
AR has extra 'meat' at the base as it is, always has, but did they ever make
AR brass with balloon heads?

ok, rant off...

Randall

 

[jaydubya]

Incidentally, the reason wadcutter bullets are loaded completely within the casing is to take up empty space left by the low powder charges. If this weren't done, the powder would slosh around, effecting burn rate so much that accuracy would be impossible. As it is, and eliminating all outside considerations, wadcutters are probably the most accurate rounds out there.

Cordially, Jack

 

[wanderinwalker]

gmhamilton3 In addition, the 9mm uses a "hotter" powder primarily to generate high pressures in a 4'' barrels. The .38 just cannot match this performance especially in a 2'' snubby. However performance is relative, both will kill you just as dead. Like you I have both along with a .45 and needless to say all 3 will be around for the next hundred years and for good reason.

Just a quick point: They frequently use the exact same powder! I load Win 231 powder into .38 Special and 9x19mm. I actually use less in the bigger .38 case.

What you get is more pressure burning X.XXgr of powder in a .38 case than in a 9mm case. Same charge + smaller space = greater pressure. Also, larger bore rounds do more work with less pressure than smaller-bore rounds.

That said, for tossing 158gr slugs, the .38 trumps the 9mm any day. For 124/125gr loads, I'll take a 9mm +P over a .38 +P. And if you have a .357 revolver, you have a whole new can of worms to open.

 

[BlindJustice]

wanderinwaker and whoever he quoted imo neither make a bit of sense
with rules of physics except yeah a larger bullet moving at the same speed
is more effective.

You put the same amount of the same powder in a larger cartrdge with more space inside and it cannot develop equal pressure, it will be less. you can't change physics.

R-

 

[doubs43]

BlindJustice, the 9mm Luger cartridge was introduced first in 1902 in the "Fat Barrel" Luger, also introduced in 1902.

The .45 Auto-Rim was made to be used in the 1917 US Army revolvers to make the half-moon clips unnecessary. Some of the revolvers were made with a step in each cylinder so that a .45ACP cartridge would work without the clips. In that instance the empties had to be individually pushed out with a pencil or similar object. Some 1917 revolvers were made with a straight cylinder and needed either the clips or the rimmed cases.

 

[BlindJustice]

ONly a very few of the M1917 Colt New Service revolvers were not counterbored for the correct chambering, none of the S&W N-frames were
made the way you incorrectly suggest. It doesn't have anything to do
with the strength of the .45 Auto RIm or how it headspaces via the rim and
not the mouth of the case like the .45 ACP. Doughboys were issued .45 ACP
in boxes where they had 8 half moon clips pre-loaded, two for the M1917 and 6 paired fit into thir bandolier that had three pockets

What does that have to do with the transition of cartrdiges from
blackpowder to smokeless ?

Randall

 

[Blakenzy]

I wonder why we don't see more snubbies in 9mm. Wouldn't it make for more compact pocket guns than .38spl, at least length wise?

 

[Radagast]

Brian Williams: It was pretty much done back in 1989 with the 9mm Federal and the Charter Arms Pit Bull. Unfortunately the 9mm Federal would chamber in old .38 S&W top break revolvers and was quickly pulled from the market.

Blakenzy Yes it would, but this would mean redesigning/engineering the revolvers to have a shorter window for the cylinder. The J & J Magnum frames are a stretch of the old I frame that the .38 S&W was chambered in many years ago. From the viewpoint of Ruger & S&W it is more viable to run with their standard frames, rather than introduce a new one. There have been short runs of 9mm chambered guns but they haven't built up any demand, possibly due to the need for moon clips.
IIRC Taurus announced a new 9mm snubbies with a short frame a couple of SHOT Shows ago, but it never made it to market in any quantity.

 

[BlindJustice]

+1 Radnagast

R-

 

[Walkalong]

In addition, the 9mm uses a "hotter" powder primarily to generate high pressures in a 4'' barrels. The .38 just cannot match this performance especially in a 2'' snubby.

It's not a "hotter" powder in the 9MM, it's just loaded to more pressure. The .38 could use any powder available and still not match the 9MM because it is loaded to a much lower pressure level, as has been posted.

 

[Deanimator]

Incidentally, the reason wadcutter bullets are loaded completely within the casing is to take up empty space left by the low powder charges.

That's A reason, not the ONLY reason.

I have a .38 Special M1911. The ONLY ammunition it can use is flush seated wadcutters. Anything longer won't fit in the magazine, much less feed.

I once went to an indoor range with a 25 yard section to zero some guns for Camp Perry, including the aforementioned Giles .38. The guy at the counter told me I couldn't shoot lead bullets, but offered to sell me some jacketed hollow points to shoot in the Giles. I just picked my stuff up and drove to another range.

 

[LightningMan]

Quote; Blakenzy I wonder why we don't see more snubbies in 9mm. Wouldn't it make for more compact pocket guns than .38spl, at least length wise?

+1 on that, it would indeed make a better CCW.

Radagast Quote;
Blakenzy Yes it would, but this would mean redesigning/engineering the revolvers to have a shorter window for the cylinder. The J & J Magnum frames are a stretch of the old I frame that the .38 S&W was chambered in many years ago. From the viewpoint of Ruger & S&W it is more viable to run with their standard frames, rather than introduce a new one.

I agree, but when Ruger came out with a totally new design with their LCR (polymer framed revolver) aimed at the CCW market, wouldn't it have made a small revolver even smaller still, without really giving up any loss of cartridge performance.

Radagast Quote; There have been short runs of 9mm chambered guns but they haven't built up any demand, possibly due to the need for moon clips.

Why can't the chambers for the revolver's cylinder headspace off the case mouth instead of the case's rim, like a .38 special? LM

 

[wanderinwalker]

BlindJustice,

You get me for trying to think and type too late for my brain!

What I meant to say, and thought I had said, is exactly what you wrote: same powder, less space, more pressure. Same powder charge in .38 case = less pressure than in a 9mm case.

Back to your regularly scheduled posting.

 

[BlindJustice]

The 9mm is a 'rimless' cartridge whereas the.38 SPecail is a rimmed cartridge. "Rimless' is something of a misnomer since a 9mm x 19 does have a rim but it's the same diameter as the rear diameter of the case proper.
FYI - the .38 Super has a 'rebated' rim where the rim diamter is less than the diameter of the case itself. Very few cartridges have rebated rims, only one
I can think of besides the .38 SUper is the .284 Winchester.

To get back to the original .38 SPecial and it's limited pressure if kkept to
SAAMI spec.. 17,000 PSI for regular and 19000 PSI for +P when it was switched from 21.5 grains of Blackpowder to smokeless powder, it left a lot of unused empty space. Some handloaders will charge the sized & primed case with a charge, then insert wadding prior to seating and crimping the bullet. THis wadding will stabilize the powder to rest at the rear of the case
nearest the primer for consistent ignition. THis technique should be considered for any of the cartrdiges which started life as blackpowder ccharged cartridges.

R-

 

[doubs43]

ONly a very few of the M1917 Colt New Service revolvers were not counterbored for the correct chambering, none of the S&W N-frames were
made the way you incorrectly suggest. It doesn't have anything to do
with the strength of the .45 Auto RIm or how it headspaces via the rim and
not the mouth of the case like the .45 ACP. Doughboys were issued .45 ACP
in boxes where they had 8 half moon clips pre-loaded, two for the M1917 and 6 paired fit into thir bandolier that had three pockets

What does that have to do with the transition of cartrdiges from
blackpowder to smokeless ? Randall

First, I didn't specify WHICH of the 1917 revolvers were, or weren't "counter bored" so your snotty reply was unnecessary. Nor did I say ANYTHING about the strength of the rimmed case.... ONLY that they were made to make the half-moon clips unnecessary. I don't recall having mentioning HOW Doughboys were issued .45ACP revolver cartridges either. I know how they were issued as I've shot WW1 issue .45ACP cartridges in half moon clips straight from the long, narrow boxes. My father had quite a few of them at one time.

YOU first brought up the .45 Auto Rim cartridges so you tell me what they have to do with black powder.

As you seem bent on being technically correct, let me point out that the 9x19mm case is a TAPERED rimless case.

Furthermore, the .38 Super case is a SEMI-RIMMED case; NOT a rebated rim. A good example of a rebated rim case is the .41 Action Express, a cartridge that didn't stay around long. The early 1911 Colts made in .38 Super headspaced on the semi-rim of the case. Newer Colt .38 Super pistols headspace on the mouth of the case.

Not everyone on these boards is as knowledgeable as others and NO ONE knows everything about all guns. The information I posted was more for those who are learning than for those who have been around for awhile. It wasn't my intention to "correct" you or engage in a debate BUT I can be as civil as anyone OR I can also come back in the same condescending tone if that's how I'm addressed.