9mm vs. 38 Spl

pbm

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I realize that 9mm and 38 spl. projectiles are very close in size but the actual 38spl. bullet is significantly longer. I'm wondering what difference this would make in a revolver. In other words would a snub nose 38 have more velocity/ energy than the same barrel length snub nose 9mm? 9mm ammo is less expensive than 38 which makes me wonder why 9mm revolvers aren't more popular?
 
Not sure of where you are getting that perspective. Most every law enforcement agency in the country is using the 9mm Glock as their service firearm. The 9mm semiautomatic holds 15 to 17 bullets according to specific model. .38 Special holds 5 bullets.
 
Because auto pistol cartridges are “rimless” 9mm revolvers require moon clips, just like .45 ACP revolvers, to keep the cases in the cylinder.

A pain, really.

While the performance between the rounds is similar, it’s a lot easier just to buy a .38 revolver.

9mm revolvers makes sense only if a person wants the same ammo across platforms.
 
I realize that 9mm and 38 spl. projectiles are very close in size but the actual 38spl. bullet is significantly longer. I'm wondering what difference this would make in a revolver. In other words would a snub nose 38 have more velocity/ energy than the same barrel length snub nose 9mm? 9mm ammo is less expensive than 38 which makes me wonder why 9mm revolvers aren't more popular?
More pressure, same weight = more velocity of course.

Why are revolver cartridges classically longer than typical modern auto ammo such as 9mm?? It has to do with design of the time, metals used in construction, and powder available at the time.

As to popularity, no clue. I think a 9mm revolver is cool. and some are making units that can shoot both.
 
Lucky Gunner has plenty of data on different loads if you want to research it.

Eh, extensive and somewhat relevant but LuckyGunner did not use the proper ballistic gelatin. The reason is cost. There are different types and the one LuckyGunner used does not meet the FBI standard for ballistic gel. It has some degree of comparison use but be aware of deficiencies.

Side note: I wish I could find this one!!!!!!!!!! Fed's did a study using ER shooting data that focused on popular LE calibers. They found the difference in death of 9, 40, 45 (357 Sig was skewed due to low data points and high % of deaths) to be statically insignificant. What they found is that those shot with either of the bullets had a much higher rate of death if shot 2 or more times.
 
More pressure, same weight = more velocity of course.

Why are revolver cartridges classically longer than typical modern auto ammo such as 9mm?? It has to do with design of the time, metals used in construction, and powder available at the time.

As to popularity, no clue. I think a 9mm revolver is cool. and some are making units that can shoot both.
Smokeless powder invented 1884.
38 special invented 1898, developed from parent case 38 long colt, first produced 1875.
9x19, first produced 1901, developed from 7.65x21, developed 1898.

The 38 case was developed from the 38 long colt, originally loaded with black powder. Case volume was necessary to accommodate the requisite charges of the day. (38 special holds 21 grains of BP but my present day light reloads are only 4 grains.) In modern times, that excessive case volume is one of the challenges with getting repeatable accuracy (at the bullseye level) out of light loads - you have no control over how the powder "lays" in the case.

Semi-auto rounds (notably, the 45 ACP and other surviving cartridges from the era, like 9mm) were developed to be shorter because John Moses Browning and his contemporaries wanted to magazine feed through the grip, not broomhandle mouser style. There's no way to fit enough black powder in these cases to get the job done. Smokeless powder was a given for firearms designers of the day - Browning, Mouser, etc.

The difference in 38 special and 357 case volume is minimal, yet 357 cases having higher pressure capacity, and can thus be loaded well beyond 9mm. Point being, the volume of the 38 special cartridge is a vestigial aspect of the cartridge.

At the heart of this, smokeless powder allowed for smaller and higher pressure cartridges that opened the door for semi-autos as we know them today as opposed to many of the anemic rounds of 100+ years ago. 32 special, etc.

In modern times, a 9mm revolver that uses moon clips can be a very practical shooter...if your armory has lots of 9mm already and you're interested in adding a revolver for novelty/training sake. That said, if you're into reloading, there are piles of 38 special brass around in the basements of widows who's husbands are no longer PPC shooters. It's an easy round to reload and lever action rifles are fun.

In either case, a 3" barrel IMO is insufficient to realize performance out of any round, but the 3" gun in my pants is better than the 4" gun left in the car.
 
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I realize that 9mm and 38 spl. projectiles are very close in size but the actual 38spl. bullet is significantly longer. I'm wondering what difference this would make in a revolver. In other words would a snub nose 38 have more velocity/ energy than the same barrel length snub nose 9mm? 9mm ammo is less expensive than 38 which makes me wonder why 9mm revolvers aren't more popular?

The bullet isn't really "longer" its the case of the 38 that has a rim and is longer. 9mm uses a .355 bullet while 38/357 uses .357 sized bullet. Nothing wrong with a 38 at all. Many a man has been dropped 6ft under with a 38. 9mm is just "better" if you'll forgive the use of better. Revolvers can be great but overall have been marginalized by semi-autos and for legitimate reasons. Higher capacity, often softer shooting, often better trigger(s), etc...

I'm blessed with a good sized armory. I have a few revolvers but overall 9mm revolver would be one of the last choices for me. 9mm in a Sig P series, Glock, HK, Shadow Systems, is more me :D
 
Not sure of where you are getting that perspective. Most every law enforcement agency in the country is using the 9mm Glock as their service firearm. The 9mm semiautomatic holds 15 to 17 bullets according to specific model. .38 Special holds 5 bullets.
I have two with 5 - one with 6
38 means more choices in a wheel gun
9mm means more choices in an auto
 
Case volume was necessary to accommodate the requisite charges.

IIRC, the 38 case was developed from the 38 long colt, in a time of black powder. Case volume was necessary to accommodate the requisite charges. In modern times, excessive case volume is one of the challenges with getting repeatable accuracy out of light loads - you have no control over how the powder "lays" in the case.
That what I was talking about about the original reason for the longer cases. Some design features never leave the gun, for one reason or the other.

Case volume was necessary to accommodate the requisite charges.
= longer cases
357 can be loaded well beyond 9mm
because it is longer.......
 
357 is longer, but that length is not irrelevant to improved ballistics. It is necessary to keep someone from putting it into a 38 special chamber. Most of the case volume is empty with modern propellants.
We are in agreement (due to it being true) to the question posed by the OP, of length comparison of the two cartridges.

I agree, the volume today is no longer needed, but as i said, some designs stay as they are, for one reason or the other.
 
I realize that 9mm and 38 spl. projectiles are very close in size but the actual 38spl. bullet is significantly longer. I'm wondering what difference this would make in a revolver. In other words would a snub nose 38 have more velocity/ energy than the same barrel length snub nose 9mm? 9mm ammo is less expensive than 38 which makes me wonder why 9mm revolvers aren't more popular?
Nah, there isn't anything special about a snub nose 38spl in terms of balistic performance over 9mm. It just costs more, has a longer cylinder. If you move to an automatic you have more capacity and easier reloads.

 
Buy a 357 instead.
I agree with the 357.

I didn't know about 'rimless' ammo which answers my question for the most part.
I live in restrictive NY which forbids me carrying in NYC where I need it most (although recent SCOTUS decisions may change that).

I haven't been into 'guns' in along time but the current state of America has me starting to rethink that.

PS: When I went on the NYPD in the summer of 1980 they were only authorized to carry 38s. The NYPD armorer sold me a new 4" S&W Model 10 for either $92 or $98...I can't remember but it was one of those prices and I'm nearly certain it was $92...imagine that. I didn't stay very long on the PD but I became a Fire Marshal in 1992 and was authorized to carry 9mm so I bought a Beretta 92 which I had to sell a couple of years later when I was promoted to Lt. (NYPD still wasn't authorized to carry 9mm at that time but that eventually changed.) I never kept up with guns but I am starting to educate myself again before deciding. While I like the higher capacity of the 9mm (although restricted to 10 rds in NY.) I like the simplicity of a (6 rd.) revolver.
 
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The differences between 9mm and 38spl have been covered, won't rehash. I believe multiple attempts at making a 9mm revolver have been done over the years, and in the end, they wound up as limited production runs--the revolver gets dropped from the catalog after a while. Niche product that few want, but at times there is enough demand to do a production run. You might be able to find one used.

IMO 38spl snubs kick hard. A lightweight gun might carry well but really be unpleasant to shoot. The same will be true for a small 9mm. Not everyone is recoil sensitive, but if you're not sure what you are after, I'll give this as a hazard to be aware of. I traded my 38spl snub for one rated for 357 for the extra heft, and only shoot 38's from it, a reasonable balance for me. I also kinda enjoy reloading and not having to chase brass is one upshot of a revolver. If it wasn't for that, I'd have gone 9mm. [Actually nothing stopping me from having both, nothing wrong with owning more than one gun, free world and all.]

I'm not sure how much POA/POI changes as one goes from 38spl->38sp+P->357 but I do believe it starts to show up real fast as distance increases (I'm minute of barn accurate and so I don't notice). I don't think the same effect shows as much in an automatic as the recoil tends to hit the hand after the round leaves the barrel--from the moment of ignition, a revolver is undergoing full recoil, but the automatic's slide has to still keep the ejection port covered until after the round leaves the barrel, thus until then, it's only the recoil spring compressing against one's hand. Whatever I've gotten wrong in this description underlines another difference between the two: an automatic tends to run with cartridges keeping to a smaller window of power, due to the need to reliably cycle. A revolver can go mild to wild (38spl wadcutters at sub 700fps to 357mag at whatever) and not care--but due to the recoil difference, may cause aiming changes.

While I like the higher capacity of the 9mm (although restricted to 10 rds in NY.) I like the simplicity of a (6 rd.) revolver.
There are 7 round 38's (S&W 686 plus?) so there is that. Think Ruger has one too. If you drop down to the 32 caliber (like 327mag) you can likewise gain a round, but at dramatically higher ammunition cost. I don't recommend that path (but have toyed with it myself). I think I've read of a few complaints about the 7 round 38's but those bugs might be worked out by now.

There's loads of reading out there. Have fun. Lots of forums. But if you are interested in carrying again, see if you get a copy of Ayoob's In the Gravest Extreme, and others like it, so as to explore the ramifications beyond just picking a holster.

If you are thinking of getting into guns again, you might want to start stockpiling ammo, last time we had a drought it lasted a few years and much hand wringing was done about it.
 
I was a cop in the last years of revolvers being the more typical police department sidearm...early 80s. Carried a State issued Model 66 with Winchester .357 Silvertips...State issued ammunition as well. There are now so many choices in excellent 9mm semi auto pistols with substantial capacity with double stack magazines, the demand for a revolver with 5-6 round capacity is minimal at best. Also, as was stated already, the need for moon clips for loading and reloading is a slower, less efficient process than slamming in a higher capacity magazine. There are 6 round snubnosed revolvers out there in .38...not many though. Older Colts, some S&Ws.
For sure 9mm is far less expensive with far more choices than .38...which is becoming less available over time.
 
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