Here's an article on Wm. M. Caldwell and Speer's device. BBHFarm Gallery :: Pressures and the Revolver, Gun Digest 1973 Edition

I just re-read that article and the findings there. One thing that jumped out was the reference on the first page to solid test barrels that had been used, presumably in Speer#8 and in Speer's ammunition development. The other thing is the correlation to what Lee Jurras was doing with Super Vel, i.e. using smaller diameter bullets, with lighter weights and longer OAL to reduce pressure.

Click here:

Alliant Powder - Reloader's Guide

Wanting to see what can and can't be done with 2400 in .38 SPL, I did some testing yesterday. In a .38 SPL case, 9.9 grains of 2400 over a 158 grain Rim Rock LSWCHP with gas check gave me the following stats on a 5 shot string out of a 2" 640-1:

Average: 826 FPS
Extreme spread: 41 FPS
standard dev: 19 FPS

This is pretty close to BB's .38 SPL standard pressure load out of the same gun. I clocked the BB 158 LSWCHP .38 SPL load at 835 FPS a few weeks ago out of the same 640-1. If you believe Speer #8 to be a reliable guide for safe reloading, my load of 9.9 grains of 2400 over a 158 LSWC would be an acceptable load in a revolver chambered in .38 SPL, as the top load listed there is 11.0 grains for a 158 grain LSWC.

Now for the +P load...

I clocked the BB .38 SPL +P load at 1030 FPS out of my 2" 640-1. 13.2 grains of 2400 over a 158 grain Rim Rock LSWCHP with gas check, in a .357 Mag case, out of the 2" 640-1 gave me results that are very similar to BB's .38 SPL +P load, as follows:

Average: 1036 FPS
Extreme spread: 45
standard dev: 18

So, that's one easy way to replicate BB's 38 SPL +P load if you have a J frame .357. However, how to replicate BB's .38 SPL +P load within any set of published .38 SPL guidelines still baffles me.

Or good Chronographs and pressure testing.

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As a matter of fact, I do!

Here is a picture of THEIR pressure testing equipment (notice the cables, not needed for CUP readings) from that manual!



FWIW

Another minor point to remember.

The powder may not be that different, but the Bullet may be completely different, than what is in the Old manual from 30 years ago. The bullet has a significant effect on pressure.

reloading manuals from the 70s list a max load of 11 grains of 2400 in the 38 special. there is no disclaimer that this powder/load shouldnt be shot in the k or j frame revolovers and those were around in the 70s. i think 2400 is a somewhat poor choice for 38 special because of the amount of poweder you have to use to get a good burn.

Here is data from the RCBS Cast Bullet Manual (1986)
38 Special
cast bullet - 38-158-SWC GC
dia. .358"
lube- RCBS Pistol
Powder - 2400
pistol primer = CCI 250 - Magnum Primer

Start Load : 9.0 grs. @ 926 fps

Maximum Load : 10.0 grs @ 1020 fps

Looking at the Lyman Cast Bullet Handbook 4th edition (2010) there is no 2400 data for a 158 gr. bullet but there is data for the 155 gr. SWC GC #358156 which I cast and load ... but get this , with 2400 the
Start Load is 7.5 grs @ 760fps to a
Max Load of 8.3 grs. @ 867 fps and a
+P Load of 8.8 grs. @ 953 fps .

Interesting to see what RCBS came up with ...

I think I would start low and work up slowly ... 7.5 grs then 8.0 grs ...then see how things shake out and go even slower 8.2 grs ...8.3 grs...slow like molasses in winter time ... be careful .

When fired case extraction starts getting sticky ... Stop !

Just go slow and test carefully ... and with near max - heavy loads use good , new or almost new brass . Hot 357 Magnum loads take a toll on brass .
Load Safe & Good Luck
Gary

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NRA Member

I will add to the 12 year old post;

that you should not wast 2400 powder in a..........

38 special, J frame, snub nose.

It is a waste of powder, tring to gain fps.

It works best with a 6" barrel, if you have one.

FWIW have usually used Bullseye and Unique for all 38 Spl. loads. 231 ball is also pretty good. Used Speer # 6,7 and 11? manuals and a few others for many years. I Never push Any load to max loads, just not worth the risks. Used 2400 in 357 Mag., 45 Colt and 44 Mag before selling them all. 44 Mag was way more than my hand(s) could take.

I use A-2400 in my 38 Spl. brass with a 158 gr. LSWC, cast and Speer swaged hollow points. I do push them a bit and even us CCI Mag primers. (the older manuals said to do so and I'm not changing now). Years ago I chronographed my load out of a 2" S&W Model 10 and got 908 fps. I was mildly impressed. Mostly use them in my 357's but the Speer hollow points are my carry load for my 2" S&W Mod. 36. Amazingly accurate and velocity is there as well enabling the Speer hollow points to expand in my 36. Never had an issue with my loads so I never looked at other powders, though some day I'm going to work with Unique to see what that'll do.

Alliant Powder - Reloader's Guide
This is the only one listed at Alliant.
38 Special +P 146 gr JHP-SWC Speer 1.37 OAL CCI 500 2400 9 grains 952 fps

d'oh 12 year old post

I was a fan of 2400 powder but more modern options are out there. Still a big fan of Bullseye and Unique.

A couple years back I was playing around testing 38spl p+ loads in a 2" bbl'd 38spl. Tried 10 different bullets (140gr to 160gr) and several different powders. The 2400 load did 900fps+ with several bullets.

Power pistol is your friend in the snubnosed 38spl p+ loads.

Many years ago, I chrono'd some .38 and .38+P loads for a friend. 2400, Unique, and Power Pistol were the powders used. All bullets were Lee 158 RNFP, Alox lube, and Fiocchi cases, CCI std primers.
Barrel length were 3" and 4" .357 guns.

2400- 10 gr 888 fps 3", 912 fps 4"
2400- 11 gr 1112 fps 3", 1111 fps 4" Book load for 38/44 replication

Unique- 5gr 861 fps 3", 882 fps 4"
Unique- 5.5 gr 946 fps 3", 985 fps 4"

PP- 5.4gr 888 fps 3", 903 fps 4"
PP- 6 gr 970 fps 3", 994 fps 4"

free info, worth what you paid for it

Nothing wrong with #2400 in the .38 Special. Newschoolers may not agree and if they have great experience with #2400, I would respect their educated opinions (based on extensive load development and testing) as valid ones.

I've tried many of the newer rifle and pistol powders that have been marketed in the last several decades. Usually, I'll revert to an older powder that provides better accuracy. Velocity is important to me but it's alway secondary to accuracy.

A few unburned powder particles is never a good reason to abandon a powder that provides top notch accuracy (and usually good velocity) except by today's fanatical fastidious shooters who have an aversion to anything remotely dirty.

Unless you are assembling low velocity target loads or using lightweight bullets the catridge wasn't really designed for, #2400 is always worth a try in the .38 Special.

Let me make some comments about some points that have come up above.

1. Modern powders are not necessarily the same as those in ye days of olde. Also, the instrumentation has become a whole lot better more recently. Piezo-electric strain gauges show pressure peaks the copper crusher system didn't. So, some load data has changed.

2. Even considering the above, published load data shows loads that were safe in their test guns or in test barrels in universal receivers. That doesn't mean they're either safe or dangerous in yours. It's wise to regard the max loads with great respect. One of the members of a defunct website made barrels for test purposes. They're made to exacting standards with minimum dimension bore, groove and chamber dimensions to provide a worst case scenario.

I developed long range rifle loads from data in one of the Sierra manuals. When a later version came out, I checked it to see if there were any changes. In the new book, my loads were out beyond maximum, yet showed only very mild pressure signs. A call to Sierra found that they had a new gun for test data. Apparently with a very different chamber & bore/groove. FWIW, after recently firing some 12 year old ammo, I found myself pulling down a couple of hundred rounds. Ended up changing powder. Not real sure what changed, maybe neck tension?

3. SAAMI protocol allowed whoever developed a cartridge to specify the test barrel length. Once chronographs became widely available, published factory velocities got much closer to real world figures. AFTER the customers realized just how much the claimed figures were distorted, SAAMI mandated handgun test barrel length that related to the guns being sold.

4. Trying to match velocities of boutique loaders is fraught with danger. First, they may have the bucks to get custom blended powders. You don't. Secondly, the phrase "meets SAAMI specs" poses a question. SAAMI has 3 pressure levels, a level production ammunition is supposed to voluntarily meet, a higher level that any sample from a given lot isn't supposed to exceed and then a level ammunition is NEVER supposed to exceed. Exactly which set of limits do they refer to? If they're doing small batch production with rigorous testing, they might be able to safely go with a higher level of pressure.

Having burned all that bandwidth, the May/June 2019 issue of American Handgunner has an article by John Taffin on 2400 in .38 Spl. He gives a load of 10 gr of 2300 under a Speer 18 GR LSWCHP. He also gives some load data for 155 gr and 170 gr cast bullets. I'd suggest you find the article online and note that the charges at the upper end are intended for use in N frame size guns.

HOLY NECROTHREAD! just noticed the OP date.

Good post, but an experienced handloader should be aware of everything you mentioned. An experienced handloader already has a paper library with current data for current use and old data for reference use. He's read them all and has far more than a basic grasp and thorough understanding of safe handloading practices and load development procedures.

A problem exists with inexperienced handloaders who don't see themselves as inexperienced and often these are the ones that think all information they need to know is available on websites and YouTube videos. Such sources are infested with non-qualified amateurs and are not properly (professionally) edited for accurate content.

This is a group of handloaders that only existed in very small factions until the days of the Internet. Lots more of them now.

When 5.6 gr of Ramshot Silhuette and a 158 gr lead swc get you 1050 fps from a 4" 38 special revolver and 17000 psi there is no need to play with 2400.

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Front sight and squeeze

FWIW, six grains of Unique under a 170-grain LSWC in .38 Special brass runs about 1070 fps from my 4" .357s. This is a max, 38/44 HD duplication load from an older Lyman manual that I loaded specifically for my M28-2. Ain't no way that's going in my K frames, including my M19-3. Too much wear on the shooter.

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Regards,

Chuck

Someone should have told me in 1968 I couldn't use 2400 in 38 Special. I went and used it for over 5 decades.

Over the years of testing 38 & 357 loads,

I deceided to save the 2400 powder for the 357 rounds and
use Unique for the shorter 38 cases, for my +P loads.

It will work in both cases, have fun.