38/357 load data disparity

[Carl N. Brown]

"I am new to reloading .38 spl/ .357 magnum and am wondering why there is such a huge gap between between 38 spl up to 20,000 psi and 357 magnum up to 35,000 psi?"

.38 Special was developed for black powder in 1898. A .38 special cartridge could hold about 20 grains of black powder developing up to 20,000 psi.
The revolvers designed to use .38 Special were designed to endure a lifetime of firing standard .38 Special ammunition.
Industry-wide specifications for .38 Special ammunition and firearms chambered to use .38 Special were set to those standards worldwide.
Smokeless powder gradually replaced black powder. It takes only about 5 grains of smokeless powder to equal the power and pressure of 20 grains black powder.
That did not make existing .38 Special firearms any stronger and did not warrant a change to standard specifications for .38 Special cartridges.
To exploit the higher power of smokeless power required a different cartridge that would not fit existing .38 Special firearms.
So in 1930 we got the .38/44 cartridge essentially a souped up .38 Special cartridge in a bigger .38/44 revolver originally designed for .44 Special.
Labelling that ammunition .38/44 "High Velocity" or "Heavy Duty" did not keep daring souls from trying it in .38 Special firearms not designed to handle it.
So in 1934-1935 Smith & Wesson and Winchester developed and marketed the .357 Magnum. After that, the.38/44 kinda faded into firearms history.

 

[Walkalong]

If I am reading the OP correctly, we maybe are being too harsh on him.

Perhaps, but safety first. Maybe they will give some feedback.

 

[film495]

Isn't the pressure for .38 Special 17,000 PSI? if you have a revolver that can handle it, +P is 20,000

unless you are shooting at criminals through car doors, and regularly fighting against miscreants that are trying to steal your pot of gold, IMHO regular .38 Special with a good bullet, and modest load, should work fine, but I'm not an expert. Lighter bullets get a little more velocity for hollow points to expand, if you are thinking in terms of self defense. .38 Special gets a bad rap sometimes, cause it was issued with Lead Round Nose bullets for decades to police departments as far as I understand, but with a modern bullet loaded correctly, is is more shootable than .357 loads which also just from my understanding, people who own a .357 which I don't, usually shoot .38 loads for the most part anyways.

I think about getting a .357 sometimes, but figure I can just shoot .38 from my Model 10and maybe carry a +P load if I want to carry it, but for me I'm happy enough shooting regular .38 special, and honestly mouse fart loads, and carry a lighter bullet factory loaded self defense cartrdige.

Whatever firearm you have should have some reference material that says if it can shoot +P or not. Personally, I don't bother with any thing +P .. if I want more nrg I'll find a different cartridge, or turn to a rifle which for the most part, simply outclasses pistol rounds regardless of what they are.

 

[denton]

I've heard (but can't vouch for) the story that one of the design criteria for the 357 was the ability to punch through a car door and still have energy comparable to an unobstructed 38. Well, that's the story, anyway.

Initial load development for the 357 was done in 38 cases, but with the bullet seated out an extra 1/8" to give more case volume. I don't know if they are still available, but at one time you could get 38 bullets with 2 cannelures 1/8" apart so you could load either 38 or 357 in a 38 case. That was a bad idea, and the world switched to the appropriate 357 case for 357 loads.

Putting a 357 load in a 38 case with 38 COL is an invitation to disaster.

 

[AJC1]

I've heard (but can't vouch for) the story that one of the design criteria for the 357 was the ability to punch through a car door and still have energy comparable to an unobstructed 38. Well, that's the story, anyway.

Initial load development for the 357 was done in 38 cases, but with the bullet seated out an extra 1/8" to give more case volume. I don't know if they are still available, but at one time you could get 38 bullets with 2 cannelures 1/8" apart so you could load either 38 or 357 in a 38 case. That was a bad idea, and the world switched to the appropriate 357 case for 357 loads.

Putting a 357 load in a 38 case with 38 COL is an invitation to disaster.

The 10mm followed FBI guidance for power and capacity. We ended up with 40 after the political hacks got done. When 357 was developed, bullet technology sucked and the more powerful cartridge offered little benefit and terrible leading issues.

 

[buck460XVR]

If I am reading the OP correctly, we maybe are being too harsh on him.

This is what I'm reading

It just seems to me the full potential of 38 spl is not being widely realized.

It reads to me, that the OP is wondering why .38 special is loaded so much weaker than .357. In reality, the full potential of .38 special is being widely realized by loading it to it's SAAMI specs, even tho, as the OP notes, there is still room in the case.

 

[Random 8]

If somebody has touched on this and I missed it, apologies. The original reason for the invention of the .357 was to make it idiot proof and impossible to chamber the hot loads in a not so hot load gun. At the time of the advent of the .357, it was absolutely possible to load .38 Special to .357 mag ballistics. It still is. It is still a bad idea if one owns a firearm chambered in .38 special or if there is any chance of any single round of .38 loaded to .357 specs being fired in a .38 chambered firearm.

I own a Henry single shot in .357 mag. The same firearm is chambered for .308 Win and other high pressure rifle rounds. It could probably handle a .357 mag with a double charge of Unique, but I'm not about to try that.

I DO have an abundance of .38 spl brass, and a very small quantity of .357 brass. I also own only .357 mag chambered handguns. I do what I do, and carefully label each box and individual cartridge as such. I recommend the OP do likewise.

 

[docbrown]

I am new to reloading .38 spl/ .357 magnum and am wondering why there is such a huge gap between between 38 spl up to 20,000 psi and 357 magnum up to 35,000 psi? Is 38-44 data meant to bridge this gap? Why wouldn't we want to load 38 cases to that higher pressure level? We know we have firearms that can tolerate that pressure so why isn't it commonplace to do so? I understand that lightly loaded 357 cases sort of pick up where 38 plus p leaves off velocity wise, but what if I only have special brass or have a gun with special chambers (assuming modern metallurgy allows the same sort of pressure tolerances regardless of cylinder length). I'm probably not going to try to blow my face off, but I am curious enough for some experimentation. I am unfamiliar with pressure signs in 38 brass so I have yet to up much hotter than published plus p data.

Personally, I would never load a 357 load in a 38 special case. Are there 38 special revolvers that could handle that hot of a load? A Security 6 chambered in 38 special likely could, (to name one - it uses the same metal/cylinder as the 357, just needs to be reamed), but the chance of one of those getting loaded in a revolver that couldn't handle it makes me cringe. I value my fingers, eyes, and face way too much to push those limits. Injury aside, I can think of few ways to more completely disassemble a Rohm 38 Special than a max load 357 Magnum cartridge.

Again, that's me - you do you. IMO, at best you will shorten the life of your 38 special while at worst, you could do some serious bodily harm to yourself or potentially others.