I'll strongly recommend what Rocky said about the Speer #8 manual. One load in particular that is extremely suspect is anything in .38 Special using 4756!!!!!! With a 125 JHP they showed a max. of 12 gr as I recall. I got cratering with the primers at 10.3 and settled on 10.0. In #9 the powder disappeared, and when it came back in #11 the maximum was more like 6 gr. If that gave 15,000 psi, then the 12.0 would be around 60,000psi. Way too much for even a .357 Magnum. I sent a letter to Speer about this and they wouldn't even acknowledge the letter.

The only good thing was that I was shooting the load in a S&W Model 12, an Airweight M&P. After something like 150-200 rounds over a couple years there was no sign of a problem with the gun. So much for the aluminum frame Smiths stretching or failing with heavy loads! I AM NOT RECOMMENDING ANYTHING, JUST SAYING WHAT WAS DONE. It was extremely dangerous and wouldn't be repeated. FWIW the 10.0 gr load with Hornady 125 JHP chronographed (several years later out of curiosity) at nearly 1350 fps in a 6" Hwy. Patrolman.

You missed the point Rocky, I don't even think they made a balloon head .38 Special and I'm almost positive they never made one in .357 Magnum. That's the reason it's a non-issue, Elmer never loaded either in a balloon head case.

Now, let's deal with SR 4756. I've been shooting 14.0 gr of SR 4756 with a 125 gr Sierra JHC in .357 Mag since 1973. It will clock at 1625 fps, just like Speer (and they weren't the only one) says out of a 6" barrel. The standard load I use in .38 Special is 10.0 gr with a 125 gr Golden Saber, but I've shot 12.0 gr without a problem. 10.0 gr clocks at 1275 fps out of a 4" M66-2 and 1340 fps out of a 6" Security Six. 12.0 gr isn't a standard load, it's probably equal to an old .38/44 at about 22,400 cup, it was developed before the +P designation was introduced. I really wouldn't be afraid to shoot it in my M14-2, but there's no need when I can just as easily shoot it in a M66. After all, it isn't exactly what I call a target load!

Here's a picture of 2 cans of SR 4756.

There is almost exactly 20 years difference in their age (1982 vs 2002). If you look closely, you'll see one is DuPont and one is IMR, but both were made in Canada. My 5# can was made in 2004, but they all perform virtually the same for me.

Here's some data I recorded in 2004, before I bought the 5# can.The load that was a problem wasn't SR 4756, it was 14.5 gr of Blue Dot (Speer #10 says the max load is 15.8 gr, Speer #13 says 13.0 gr is max), an obvious overload for my gun with sticky extraction and very little velocity gain over 13.0 gr (my velocity was 120 fps faster than Speer's with 13.0 gr, but the .22 LR results basically confirmed the data I got. Of course, I was using R-P brass, not Speer brass like they were).

Now, the moral of this whole thing is, the later reloading books are supposed right and the earlier ones are wrong, but the data I got seems to indicate that may not be true. I haven't sampled every lot of powder available, but neither has anyone else, besides the particular manufacturer. None of it is law, that's why IMR, Hercules and Accurate specifed on the cover of their manuals, "Reloader's Guide". Some of their guidance is based on an ever changing SAAMI maximum pressure, but the strength of the existing guns hasn't changed.

An M66-2 was designed to handle 46,000 cup loads, not 35,000 psi loads and an M14-2 was designed for at least 18,900 cup. You can choke them down if you want, but I think I'll let them do what they were designed for.

14.0 grains of SR 4756 is way over IMR, Speer #11 and Hodgdon #26 data for the .357. I won't suggest anyone else trying your load.

Bye
Jack

Well of course it's way over what they post now. That's part of the issue here. Speer #13 doesn't publish anything that will break 1450 fps with a 125 gr bullet in .357 Mag, which doesn't even compare well with the 158 gr lead they were shooting in the '50s.

From the Starline Brass website:

"38 SPL+P has no difference from the standard 38 SPL, other than headstamp designation for load segregation. Due to standard case design, will handle +P pressures with no problems."

Ralph

Ralph, I believe that may be true for Starline brass, but not for others. If Starline chose to standardize on a thicker case web (to +P standards) to simplify manufacture, but not to headstamp them that way, that has no effect on how other manufacturers make or stamp them. All Starline brass I've tested produces slightly higher loads than brass from other makers, so perhaps they design all their cases to +P criteria. But others do not.

Paul, you may be right about there never being a balloon-head .38 case. But in your original reference to Keith, you didn't say "his .38 loads" you just said "his loads" - which I interpreted to include all his heavy 2400 loads in all calibers. And no matter, because it is still true that none of the components he used then in any caliber are identical to what are being made now - so the data and Keith's loads are NOT safe today.

Finally, just because a certain reveolver is made to handle a given pressure (a number which you are supposing, since NO manufacturer ever says what the design limits of their guns are), it does not mean that a given individual sample of that gun may be microscopically flawed, or that it could withstand maximum loads forever even if it weren't. You are also guessing about what pressures your loads develop, unless you've had them lab-tested. You've gotten away with them so far, but the next trigger pull might be a loud surprise.

And last of all, you aren't the only one reading posts like this. There are other reloaders of other skill levels, and other guns in use. I think my advice is applicable to all of them: never exceed loads shown in the most current manual, using the components listed.

__________________
To see my books and articles, just Google my name.

Sorry if I offended you, but I have two choices when anyone posts loads that are significantly over any recently published data. Either post a warning or delete the post.

Bye
Jack

Jack,

No offense taken.

Rocky,

The thread is about .38 Specials not .44 Specials or .45 Auto Rim or even .45 Colt where there certainly were balloon head cases.

The lot of 2400 you buy in Utah probably isn't the same lot as what I buy in Texas, so no components are ever the exact same.

We can also say the proof load used in the factory may stress the gun enough that the next shot will be the big kaboom too. I suppose it's something that can't be determined without conducting destructive testing, but then the gun has been destroyed by testing and isn't good for anything again.

Reloading can be a dangerous passtime if it isn't done properly, but you can rest assured Speer would have never published #7 and #8 if they were blowing up guns with their loads.

I have never ruptured a .38 Special or .357 Magnum, but I can't make that claim for 9mm in unsupported chambers and I use modern published loads in 9mm!

I think I have a few +P .38 Specials that aren't Starline, so I'll check a few with an ID gauge and see if they are thicker than regular .38 Specials. I'll report my findings.

Well, that was an interesting exercise.

I used an inside gauge that was then measured with an insulated micrometer that is accurate to .0001". The inside gauge was inserted all the way to the bottom of the case, opened and locked. The OD was just a straight forward outside measurement.

I managed to find 1 piece of .38 Special W-W +P and compared it to a random .38 Special regular nickeled case, to match nickeled cases with each other. The ID of the W-W +P was .3445" and the ID of the regular W-W was .3449". The OD of both was the same at .3779".

Then I hit a gold mine of R-P cases and again compared nickeled cases. The ID of the +P was .3303" and .3309", where the regular cases were .3361" and .3385". The OD was .3760" and .3759" for the +P and .3758" and .3754" for the regular cases.

The thickness of the W-W was .0334" and .033", but the thickness of the R-P was .0457", .045", .0397", .0369".

I would conclude the W-W was the same thickness regardless of what was on the headstamp, but R-P was different between the two and even the regular R-P was thicker than the W-W.

Of course, thickness isn't really an indication of strength. Olin Cartridge Alloy #260 can be obtained in a range of tensile strength and yield strengths. They have a pdf file on their website with the data ranges.

Even to assume cartridges from the same manufacturer are the same strength is possibly an error. The minimum tensile strength is 45,000 psi and the maximum is 104,000 psi. The yield strength ranges from 21,000 psi to 89,000 psi.
Olin Alloy pdf

I got to thinking about those brass specifications and I don't think a good case can be made for restricting the .38 Special to 17,000 psi! The minimum tensile strength for cartridge brass is 45,000 psi and if you only allow 50%, that's still 22,500 psi.

I also got to thinking about loading manuals, especially when one of the moderators on www.handloads.com mentioned an article he was thinking about writing on pressure signs. He referenced Speer #13 and this is a response I made.I suppose you know I'm not just picking on Speer, because all the manuals say the same thing, regardless of who publishes it (except Lee Modern Reloading and they just quote the use of generic components and let you blaze away!).